SPARK-1251 Support for optimizing and executing structured queries

This pull request adds support to Spark for working with structured data using a simple SQL dialect, HiveQL and a Scala Query DSL.

*This is being contributed as a new __alpha component__ to Spark and does not modify Spark core or other components.*

The code is broken into three primary components:
 - Catalyst (sql/catalyst) - An implementation-agnostic framework for manipulating trees of relational operators and expressions.
 - Execution (sql/core) - A query planner / execution engine for translating Catalyst’s logical query plans into Spark RDDs.  This component also includes a new public interface, SqlContext, that allows users to execute SQL or structured scala queries against existing RDDs and Parquet files.
 - Hive Metastore Support (sql/hive) - An extension of SqlContext called HiveContext that allows users to write queries using a subset of HiveQL and access data from a Hive Metastore using Hive SerDes.  There are also wrappers that allows users to run queries that include Hive UDFs, UDAFs, and UDTFs.

A more complete design of this new component can be found in [the associated JIRA](https://spark-project.atlassian.net/browse/SPARK-1251).

[An updated version of the Spark documentation, including API Docs for all three sub-components,](http://people.apache.org/~pwendell/catalyst-docs/sql-programming-guide.html) is also available for review.

With this PR comes support for inferring the schema of existing RDDs that contain case classes.  Using this information, developers can now express structured queries that are automatically compiled into RDD operations.

```scala
// Define the schema using a case class.
case class Person(name: String, age: Int)
val people: RDD[Person] =
  sc.textFile("people.txt").map(_.split(",")).map(p => Person(p(0), p(1).toInt))

// The following is the same as 'SELECT name FROM people WHERE age >= 10 && age <= 19'
val teenagers = people.where('age >= 10).where('age <= 19).select('name).toRdd
```

RDDs can also be registered as Tables, allowing SQL queries to be written over them.
```scala
people.registerAsTable("people")
val teenagers = sql("SELECT name FROM people WHERE age >= 10 && age <= 19")
```

The results of queries are themselves RDDs and support standard RDD operations:
```scala
teenagers.map(t => "Name: " + t(0)).collect().foreach(println)
```

Finally, with the optional Hive support, users can read and write data located in existing Apache Hive deployments using HiveQL.
```scala
sql("CREATE TABLE IF NOT EXISTS src (key INT, value STRING)")
sql("LOAD DATA LOCAL INPATH 'src/main/resources/kv1.txt' INTO TABLE src")

// Queries are expressed in HiveQL
sql("SELECT key, value FROM src").collect().foreach(println)
```

## Relationship to Shark

Unlike Shark, Spark SQL does not act as a drop in replacement for Hive or the HiveServer. Instead this new feature is intended to make it easier for Spark developers to run queries over structured data, using either SQL or the query DSL. After this sub-project graduates from Alpha status it will likely become a new optimizer/backend for the Shark project.

Author: Michael Armbrust <michael@databricks.com>
Author: Yin Huai <huaiyin.thu@gmail.com>
Author: Reynold Xin <rxin@apache.org>
Author: Lian, Cheng <rhythm.mail@gmail.com>
Author: Andre Schumacher <andre.schumacher@iki.fi>
Author: Yin Huai <huai@cse.ohio-state.edu>
Author: Timothy Chen <tnachen@gmail.com>
Author: Cheng Lian <lian.cs.zju@gmail.com>
Author: Timothy Chen <tnachen@apache.org>
Author: Henry Cook <henry.m.cook+github@gmail.com>
Author: Mark Hamstra <markhamstra@gmail.com>

Closes #146 from marmbrus/catalyst and squashes the following commits:

458bd1b [Michael Armbrust] Update people.txt
0d638c3 [Michael Armbrust] Typo fix from @ash211.
bdab185 [Michael Armbrust] Address another round of comments: * Doc examples can now copy/paste into spark-shell. * SQLContext is serializable * Minor parser bugs fixed * Self-joins of RDDs now handled correctly. * Removed deprecated examples * Removed deprecated parquet docs * Made more of the API private * Copied all the DSLQuery tests and rewrote them as SQLQueryTests
778299a [Michael Armbrust] Fix some old links to spark-project.org
fead0b6 [Michael Armbrust] Create a new RDD type, SchemaRDD, that is now the return type for all SQL operations.  This improves the old API by reducing the number of implicits that are required, and avoids throwing away schema information when returning an RDD to the user.  This change also makes it slightly less verbose to run language integrated queries.
fee847b [Michael Armbrust] Merge remote-tracking branch 'origin/master' into catalyst, integrating changes to serialization for ShuffledRDD.
48a99bc [Michael Armbrust] Address first round of feedback.
461581c [Michael Armbrust] Blacklist test that depends on JVM specific rounding behaviour
adcf1a4 [Henry Cook] Update sql-programming-guide.md
9dffbfa [Michael Armbrust] Style fixes. Add downloading of test cases to jenkins.
6978dd8 [Michael Armbrust] update docs, add apache license
1d0eb63 [Michael Armbrust] update changes with spark core
e5e1d6b [Michael Armbrust] Remove travis configuration.
c2efad6 [Michael Armbrust] First draft of SQL documentation.
013f62a [Michael Armbrust] Fix documentation / code style.
c01470f [Michael Armbrust] Clean up example
2f22454 [Michael Armbrust] WIP: Parquet example.
ce8073b [Michael Armbrust] clean up implicits.
f7d992d [Michael Armbrust] Naming / spelling.
9eb0294 [Michael Armbrust] Bring expressions implicits into SqlContext.
d2d9678 [Michael Armbrust] Make sure hive isn't in the assembly jar.  Create a separate, optional Hive assembly that is used when present.
8b35e0a [Michael Armbrust] address feedback, work on DSL
5d71074 [Michael Armbrust] Merge pull request #62 from AndreSchumacher/parquet_file_fixes
f93aa39 [Andre Schumacher] Better handling of path names in ParquetRelation
1a4bbd9 [Michael Armbrust] Merge pull request #60 from marmbrus/maven
3386e4f [Michael Armbrust] Merge pull request #58 from AndreSchumacher/parquet_fixes
3447c3e [Michael Armbrust] Don't override the metastore / warehouse in non-local/test hive context.
7233a74 [Michael Armbrust] initial support for maven builds
f0ba39e [Michael Armbrust] Merge remote-tracking branch 'origin/master' into maven
7386a9f [Michael Armbrust] Initial example programs using spark sql.
aeaef54 [Andre Schumacher] Removing unnecessary Row copying and reverting some changes to MutableRow
7ca4b4e [Andre Schumacher] Improving checks in Parquet tests
5bacdc0 [Andre Schumacher] Moving towards mutable rows inside ParquetRowSupport
54637ec [Andre Schumacher] First part of second round of code review feedback
c2a658d [Michael Armbrust] Merge pull request #55 from marmbrus/mutableRows
ba28849 [Michael Armbrust] code review comments.
d994333 [Michael Armbrust] Remove copies before shuffle, this required changing the default shuffle serialization.
9049cf0 [Michael Armbrust] Extend MutablePair interface to support easy syntax for in-place updates.  Also add a constructor so that it can be serialized out-of-the-box.
959bdf0 [Michael Armbrust] Don't silently swallow all KryoExceptions, only the one that indicates the end of a stream.
d371393 [Michael Armbrust] Add a framework for dealing with mutable rows to reduce the number of object allocations that occur in the critical path.
c9f8fb3 [Michael Armbrust] Merge pull request #53 from AndreSchumacher/parquet_support
3c3f962 [Michael Armbrust] Fix a bug due to array reuse.  This will need to be revisited after we merge the mutable row PR.
7d0f13e [Michael Armbrust] Update parquet support with master.
9d419a6 [Michael Armbrust] Merge remote-tracking branch 'catalyst/catalystIntegration' into parquet_support
0040ae6 [Andre Schumacher] Feedback from code review
1ce01c7 [Michael Armbrust] Merge pull request #56 from liancheng/unapplySeqForRow
70e489d [Cheng Lian] Fixed a spelling typo
6d315bb [Cheng Lian] Added Row.unapplySeq to extract fields from a Row object.
8d5da5e [Michael Armbrust] modify compute-classpath.sh to include datanucleus jars explicitly
99e61fb [Michael Armbrust] Merge pull request #51 from marmbrus/expressionEval
7b9d142 [Michael Armbrust] Update travis to increase permgen size.
da9afbd [Michael Armbrust] Add byte wrappers for hive UDFS.
6fdefe6 [Michael Armbrust] Port sbt improvements from master.
296fe50 [Michael Armbrust] Address review feedback.
d7fbc3a [Michael Armbrust] Several performance enhancements and simplifications of the expression evaluation framework.
3bda72d [Andre Schumacher] Adding license banner to new files
3ac9eb0 [Andre Schumacher] Rebasing to new main branch
c863bed [Andre Schumacher] Codestyle checks
61e3bfb [Andre Schumacher] Adding WriteToFile operator and rewriting ParquetQuerySuite
3321195 [Andre Schumacher] Fixing one import in ParquetQueryTests.scala
3a0a552 [Andre Schumacher] Reorganizing Parquet table operations
18fdc44 [Andre Schumacher] Reworking Parquet metadata in relation and adding CREATE TABLE AS for Parquet tables
75262ee [Andre Schumacher] Integrating operations on Parquet files into SharkStrategies
f347273 [Andre Schumacher] Adding ParquetMetaData extraction, fixing schema projection
6a6bf98 [Andre Schumacher] Added column projections to ParquetTableScan
0f17d7b [Andre Schumacher] Rewriting ParquetRelation tests with RowWriteSupport
a11e364 [Andre Schumacher] Adding Parquet RowWriteSupport
6ad05b3 [Andre Schumacher] Moving ParquetRelation to spark.sql core
eb0e521 [Andre Schumacher] Fixing package names and other problems that came up after the rebase
99a9209 [Andre Schumacher] Expanding ParquetQueryTests to cover all primitive types
b33e47e [Andre Schumacher] First commit of Parquet import of primitive column types
c334386 [Michael Armbrust] Initial support for generating schema's based on case classes.
608a29e [Michael Armbrust] Add hive as a repl dependency
7413ac2 [Michael Armbrust] make test downloading quieter.
4d57d0e [Michael Armbrust] Fix test execution on travis.
5f2963c [Michael Armbrust] naming and continuous compilation fixes.
f5e7492 [Michael Armbrust] Add Apache license.  Make naming more consistent.
3ac9416 [Michael Armbrust] Merge support for working with schema-ed RDDs using catalyst in as a spark subproject.
2225431 [Michael Armbrust] Merge pull request #48 from marmbrus/minorFixes
d393d2a [Michael Armbrust] Review Comments: Add comment to map that adds a sub query.
24eaa79 [Michael Armbrust] fix > 100 chars
6e04e5b [Michael Armbrust] Add insertIntoTable to the DSL.
df88f01 [Michael Armbrust] add a simple test for aggregation
18a861b [Michael Armbrust] Correctly convert nested products into nested rows when turning scala data into catalyst data.
b922511 [Michael Armbrust] Fix insertion of nested types into hive tables.
5fe7de4 [Michael Armbrust] Move table creation out of rule into a separate function.
a430895 [Michael Armbrust] Planning for logical Repartition operators.
532dd37 [Michael Armbrust] Allow the local warehouse path to be specified.
4905b2b [Michael Armbrust] Add more efficient TopK that avoids global sort for logical Sort => StopAfter.
8c01c24 [Michael Armbrust] Move definition of Row out of execution to top level sql package.
c9116a6 [Michael Armbrust] 
Add combiner to avoid NPE when spark performs external aggregation.
29effad [Michael Armbrust] Include alias in attributes that are produced by overridden tables.
9990ec7 [Michael Armbrust] Merge pull request #28 from liancheng/columnPruning
f22df3a [Michael Armbrust] Merge pull request #37 from yhuai/SerDe
cf4db59 [Lian, Cheng] Added golden answers for PruningSuite
54f165b [Lian, Cheng] Fixed spelling typo in two golden answer file names
2682f72 [Lian, Cheng] Merge remote-tracking branch 'origin/master' into columnPruning
c5a4fab [Lian, Cheng] Merge branch 'master' into columnPruning
f670c8c [Yin Huai] Throw a NotImplementedError for not supported clauses in a CTAS query.
128a9f8 [Yin Huai] Minor changes.
017872c [Yin Huai] Remove stats20 from whitelist.
a1a4776 [Yin Huai] Update comments.
feb022c [Yin Huai] Partitioning key should be case insensitive.
555fb1d [Yin Huai] Correctly set the extension for a text file.
d00260b [Yin Huai] Strips backticks from partition keys.
334aace [Yin Huai] New golden files.
a40d6d6 [Yin Huai] Loading the static partition specified in a INSERT INTO/OVERWRITE query.
428aff5 [Yin Huai] Distinguish `INSERT INTO` and `INSERT OVERWRITE`.
eea75c5 [Yin Huai] Correctly set codec.
45ffb86 [Yin Huai] Merge remote-tracking branch 'upstream/master' into SerDeNew
e089627 [Yin Huai] Code style.
563bb22 [Yin Huai] Set compression info in FileSinkDesc.
35c9a8a [Michael Armbrust] Merge pull request #46 from marmbrus/reviewFeedback
bdab5ed [Yin Huai] Add a TODO for loading data into partitioned tables.
5495fab [Yin Huai] Remove cloneRecords which is no longer needed.
1596e1b [Yin Huai] Cleanup imports to make IntelliJ happy.
3bb272d [Michael Armbrust] move org.apache.spark.sql package.scala to the correct location.
8506c17 [Michael Armbrust] Address review feedback.
3cb4f2e [Michael Armbrust] Merge pull request #45 from tnachen/master
9ad474d [Michael Armbrust] Merge pull request #44 from marmbrus/sampling
566fd66 [Timothy Chen] Whitelist tests and add support for Binary type
69adf72 [Yin Huai] Set cloneRecords to false.
a9c3188 [Timothy Chen] Fix udaf struct return
346f828 [Yin Huai] Move SharkHadoopWriter to the correct location.
59e37a3 [Yin Huai] Merge remote-tracking branch 'upstream/master' into SerDeNew
ed3a1d1 [Yin Huai] Load data directly into Hive.
7f206b5 [Michael Armbrust] Add support for hive TABLESAMPLE PERCENT.
b6de691 [Michael Armbrust] Merge pull request #43 from liancheng/fixMakefile
1f6260d [Lian, Cheng] Fixed package name and test suite name in Makefile
5ae010f [Michael Armbrust] Merge pull request #42 from markhamstra/non-ascii
678341a [Mark Hamstra] Replaced non-ascii text
887f928 [Yin Huai] Merge remote-tracking branch 'upstream/master' into SerDeNew
1f7d00a [Reynold Xin] Merge pull request #41 from marmbrus/splitComponents
7588a57 [Michael Armbrust] Break into 3 major components and move everything into the org.apache.spark.sql package.
bc9a12c [Michael Armbrust] Move hive test files.
5720d2b [Lian, Cheng] Fixed comment typo
f0c3742 [Lian, Cheng] Refactored PhysicalOperation
f235914 [Lian, Cheng] Test case udf_regex and udf_like need BooleanWritable registered
cf691df [Lian, Cheng] Added the PhysicalOperation to generalize ColumnPrunings
2407a21 [Lian, Cheng] Added optimized logical plan to debugging output
a7ad058 [Michael Armbrust] Merge pull request #40 from marmbrus/includeGoldens
9329820 [Michael Armbrust] add golden answer files to repository
dce0593 [Michael Armbrust] move golden answer to the source code directory.
964368f [Michael Armbrust] Merge pull request #39 from marmbrus/lateralView
7785ee6 [Michael Armbrust] Tighten visibility based on comments.
341116c [Michael Armbrust] address comments.
0e6c1d7 [Reynold Xin] Merge pull request #38 from yhuai/parseDBNameInCTAS
2897deb [Michael Armbrust] fix scaladoc
7123225 [Yin Huai] Correctly parse the db name and table name in INSERT queries.
b376d15 [Michael Armbrust] fix newlines at EOF
5cc367c [Michael Armbrust] use berkeley instead of cloudbees
ff5ea3f [Michael Armbrust] new golden
db92adc [Michael Armbrust] more tests passing. clean up logging.
740febb [Michael Armbrust] Tests for tgfs.
0ce61b0 [Michael Armbrust] Docs for GenericHiveUdtf.
ba8897f [Michael Armbrust] Merge remote-tracking branch 'yin/parseDBNameInCTAS' into lateralView
dd00b7e [Michael Armbrust] initial implementation of generators.
ea76cf9 [Michael Armbrust] Add NoRelation to planner.
bea4b7f [Michael Armbrust] Add SumDistinct.
016b489 [Michael Armbrust] fix typo.
acb9566 [Michael Armbrust] Correctly type attributes of CTAS.
8841eb8 [Michael Armbrust] Rename Transform -> ScriptTransformation.
02ff8e4 [Yin Huai] Correctly parse the db name and table name in a CTAS query.
5e4d9b4 [Michael Armbrust] Merge pull request #35 from marmbrus/smallFixes
5479066 [Reynold Xin] Merge pull request #36 from marmbrus/partialAgg
8017afb [Michael Armbrust] fix copy paste error.
dc6353b [Michael Armbrust] turn off deprecation
cab1a84 [Michael Armbrust] Fix PartialAggregate inheritance.
883006d [Michael Armbrust] improve tests.
32b615b [Michael Armbrust] add override to asPartial.
e1999f9 [Yin Huai] Use Deserializer and Serializer instead of AbstractSerDe.
f94345c [Michael Armbrust] fix doc link
d8cb805 [Michael Armbrust] Implement partial aggregation.
ccdb07a [Michael Armbrust] Fix bug where averages of strings are turned into sums of strings.  Remove a blank line.
b4be6a5 [Michael Armbrust] better logging when applying rules.
67128b8 [Reynold Xin] Merge pull request #30 from marmbrus/complex
cb57459 [Michael Armbrust] blacklist machine specific test.
2f27604 [Michael Armbrust] Address comments / style errors.
389525d [Michael Armbrust] update golden, blacklist mr.
e3c10bd [Michael Armbrust] update whitelist.
44d343c [Michael Armbrust] Merge remote-tracking branch 'databricks/master' into complex
42ec4af [Michael Armbrust] improve complex type support in hive udfs/udafs.
ab5bff3 [Michael Armbrust] Support for get item of map types.
1679554 [Michael Armbrust] add toString for if and IS NOT NULL.
ab9a131 [Michael Armbrust] when UDFs fail they should return null.
25288d0 [Michael Armbrust] Implement [] for arrays and maps.
e7933e9 [Michael Armbrust] fix casting bug when working with fractional expressions.
010accb [Michael Armbrust] add tinyint to metastore type parser.
7a0f543 [Michael Armbrust] Avoid propagating types from unresolved nodes.
ac9d7de [Michael Armbrust] Resolve *s in Transform clauses.
692a477 [Michael Armbrust] Support for wrapping arrays to be written into hive tables.
92e4158 [Reynold Xin] Merge pull request #32 from marmbrus/tooManyProjects
9c06778 [Michael Armbrust] fix serialization issues, add JavaStringObjectInspector.
72a003d [Michael Armbrust] revert regex change
7661b6c [Michael Armbrust] blacklist machines specific tests
aa430e7 [Michael Armbrust] Update .travis.yml
e4def6b [Michael Armbrust] set dataType for HiveGenericUdfs.
5e54aa6 [Michael Armbrust] quotes for struct field names.
bbec500 [Michael Armbrust] update test coverage, new golden
3734a94 [Michael Armbrust] only quote string types.
3f9e519 [Michael Armbrust] use names w/ boolean args
5b3d2c8 [Michael Armbrust] implement distinct.
5b33216 [Michael Armbrust] work on decimal support.
2c6deb3 [Michael Armbrust] improve printing compatibility.
35a70fb [Michael Armbrust] multi-letter field names.
a9388fb [Michael Armbrust] printing for map types.
c3feda7 [Michael Armbrust] use toArray.
c654f19 [Michael Armbrust] Support for list and maps in hive table scan.
cf8d992 [Michael Armbrust] Use built in functions for creating temp directory.
1579eec [Michael Armbrust] Only cast unresolved inserts.
6420c7c [Michael Armbrust] Memoize the ordinal in the GetField expression.
da7ae9d [Michael Armbrust] Add boolean writable that was breaking udf_regexp test.  Not sure how this was passing before...
6709441 [Michael Armbrust] Evaluation for accessing nested fields.
dc6463a [Michael Armbrust] Support for resolving access to nested fields using "." notation.
d670e41 [Michael Armbrust] Print nested fields like hive does.
efa7217 [Michael Armbrust] Support for reading structs in HiveTableScan.
9c22b4e [Michael Armbrust] Support for parsing nested types.
82163e3 [Michael Armbrust] special case handling of partitionKeys when casting insert into tables
ea6f37f [Michael Armbrust] fix style.
7845364 [Michael Armbrust] deactivate concurrent test.
b649c20 [Michael Armbrust] fix test logging / caching.
1590568 [Michael Armbrust] add log4j.properties
19bfd74 [Michael Armbrust] store hive output in circular buffer
dfb67aa [Michael Armbrust] add test case
cb775ac [Michael Armbrust] get rid of SharkContext singleton
2de89d0 [Michael Armbrust] Merge pull request #13 from tnachen/master
63003e9 [Michael Armbrust] Fix spacing.
41b41f3 [Michael Armbrust] Only cast unresolved inserts.
6eb5960 [Michael Armbrust] Merge remote-tracking branch 'databricks/master' into udafs
5b7afd8 [Michael Armbrust] Merge pull request #10 from yhuai/exchangeOperator
b1151a8 [Timothy Chen] Fix load data regex
8e0931f [Michael Armbrust] Cast to avoid using deprecated hive API.
e079f2b [Timothy Chen] Add GenericUDAF wrapper and HiveUDAFFunction
45b334b [Yin Huai] fix comments
235cbb4 [Yin Huai] Merge remote-tracking branch 'upstream/master' into exchangeOperator
fc67b50 [Yin Huai] Check for a Sort operator with the global flag set instead of an Exchange operator with a RangePartitioning.
6015f93 [Michael Armbrust] Merge pull request #29 from rxin/style
271e483 [Michael Armbrust] Update build status icon.
d3a3d48 [Michael Armbrust] add testing to travis
807b2d7 [Michael Armbrust] check style and publish docs with travis
d20b565 [Michael Armbrust] fix if style
bce024d [Michael Armbrust] Merge remote-tracking branch 'databricks/master' into style Disable if brace checking as it errors in single line functional cases unlike the style guide.
d91e276 [Michael Armbrust] Remove dependence on HIVE_HOME for running tests.  This was done by moving all the hive query test (from branch-0.12) and data files into src/test/hive.  These are used by default when HIVE_HOME is not set.
f47c2f6 [Yin Huai] set outputPartitioning in BroadcastNestedLoopJoin
41bbee6 [Yin Huai] Merge remote-tracking branch 'upstream/master' into exchangeOperator
7e24436 [Reynold Xin] Removed dependency on JDK 7 (nio.file).
5c1e600 [Reynold Xin] Added hash code implementation for AttributeReference
7213a2c [Reynold Xin] style fix for Hive.scala.
08e4d05 [Reynold Xin] First round of style cleanup.
605255e [Reynold Xin] Added scalastyle checker.
61e729c [Lian, Cheng] Added ColumnPrunings strategy and test cases
2486fb7 [Lian, Cheng] Fixed spelling
8ee41be [Lian, Cheng] Minor refactoring
ebb56fa [Michael Armbrust] add travis config
4c89d6e [Reynold Xin] Merge pull request #27 from marmbrus/moreTests
d4f539a [Michael Armbrust] blacklist mr and user specific tests.
677eb07 [Michael Armbrust] Update test whitelist.
5dab0bc [Michael Armbrust] Merge pull request #26 from liancheng/serdeAndPartitionPruning
c263c84 [Michael Armbrust] Only push predicates into partitioned table scans.
ab77882 [Michael Armbrust] upgrade spark to RC5.
c98ede5 [Lian, Cheng] Response to comments from @marmbrus
83d4520 [Yin Huai] marmbrus's comments
70994a3 [Lian, Cheng] Revert unnecessary Scaladoc changes
9ebff47 [Yin Huai] remove unnecessary .toSeq
e811d1a [Yin Huai] markhamstra's comments
4802f69 [Yin Huai] The outputPartitioning of a UnaryNode inherits its child's outputPartitioning by default. Also, update the logic in AddExchange to avoid unnecessary shuffling operations.
040fbdf [Yin Huai] AddExchange is the only place to add Exchange operators.
9fb357a [Yin Huai] use getSpecifiedDistribution to create Distribution. ClusteredDistribution and OrderedDistribution do not take Nil as inptu expressions.
e9347fc [Michael Armbrust] Remove broken scaladoc links.
99c6707 [Michael Armbrust] upgrade spark
57799ad [Lian, Cheng] Added special treat for HiveVarchar in InsertIntoHiveTable
cb49af0 [Lian, Cheng] Fixed Scaladoc links
4e5e4d4 [Lian, Cheng] Added PreInsertionCasts to do necessary casting before insertion
111ffdc [Lian, Cheng] More comments and minor reformatting
9e0d840 [Lian, Cheng] Added partition pruning optimization
761bbb8 [Lian, Cheng] Generalized BindReferences to run against any query plan
04eb5da [Yin Huai] Merge remote-tracking branch 'upstream/master' into exchangeOperator
9dd3b26 [Michael Armbrust] Fix scaladoc.
6f44cac [Lian, Cheng] Made TableReader & HadoopTableReader private to catalyst
7c92a41 [Lian, Cheng] Added Hive SerDe support
ce5fdd6 [Yin Huai] Merge remote-tracking branch 'upstream/master' into exchangeOperator
2957f31 [Yin Huai] addressed comments on PR
907db68 [Michael Armbrust] Space after while.
04573a0 [Reynold Xin] Merge pull request #24 from marmbrus/binaryCasts
4e50679 [Reynold Xin] Merge pull request #25 from marmbrus/rowOrderingWhile
5bc1dc2 [Yin Huai] Merge remote-tracking branch 'upstream/master' into exchangeOperator
be1fff7 [Michael Armbrust] Replace foreach with while in RowOrdering. Fixes #23
fd084a4 [Michael Armbrust] implement casts binary <=> string.
0b31176 [Michael Armbrust] Merge pull request #22 from rxin/type
548e479 [Yin Huai] merge master into exchangeOperator and fix code style
5b11db0 [Reynold Xin] Added Void to Boolean type widening.
9e3d989 [Reynold Xin] Made HiveTypeCoercion.WidenTypes more clear.
9bb1979 [Reynold Xin] Merge pull request #19 from marmbrus/variadicUnion
a2beb38 [Michael Armbrust] Merge pull request #21 from liancheng/fixIssue20
b20a4d4 [Lian, Cheng] Fix issue #20
6d6cb58 [Michael Armbrust] add source links that point to github to the scala doc.
4285962 [Michael Armbrust] Remove temporary test cases
167162f [Michael Armbrust] more merge errors, cleanup.
e170ccf [Michael Armbrust] Improve documentation and remove some spurious changes that were introduced by the merge.
6377d0b [Michael Armbrust] Drop empty files, fix if ().
c0b0e60 [Michael Armbrust] cleanup broken doc links.
330a88b [Michael Armbrust] Fix bugs in AddExchange.
4f345f2 [Michael Armbrust] Remove SortKey, use RowOrdering.
043e296 [Michael Armbrust] Make physical union nodes variadic.
ece15e1 [Michael Armbrust] update unit tests
5c89d2e [Michael Armbrust] Merge remote-tracking branch 'databricks/master' into exchangeOperator Fix deprecated use of combineValuesByKey. Get rid of test where the answer is dependent on the plan execution width.
9804eb5 [Michael Armbrust] upgrade spark
053a371 [Michael Armbrust] Merge pull request #15 from marmbrus/orderedRow
5ab18be [Michael Armbrust] Merge remote-tracking branch 'databricks/master' into orderedRow
ca2ff68 [Michael Armbrust] Merge pull request #17 from marmbrus/unionTypes
bf9161c [Michael Armbrust] Merge pull request #18 from marmbrus/noSparkAgg
563053f [Michael Armbrust] Address @rxin's comments.
6537c66 [Michael Armbrust] Address @rxin's comments.
2a76fc6 [Michael Armbrust] add notes from @rxin.
685bfa1 [Michael Armbrust] fix spelling
69ed98f [Michael Armbrust] Output a single row for empty Aggregations with no grouping expressions.
7859a86 [Michael Armbrust] Remove SparkAggregate.  Its kinda broken and breaks RDD lineage.
fc22e01 [Michael Armbrust] whitelist newly passing union test.
3f547b8 [Michael Armbrust] Add support for widening types in unions.
53b95f8 [Michael Armbrust] coercion should not occur until children are resolved.
b892e32 [Michael Armbrust] Union is not resolved until the types match up.
95ab382 [Michael Armbrust] Use resolved instead of custom function.  This is better because some nodes override the notion of resolved.
81a109d [Michael Armbrust] fix link.
f143f61 [Michael Armbrust] Implement sampling.  Fixes a flaky test where the JVM notices that RAND as a Comparison method "violates its general contract!"
6cd442b [Michael Armbrust] Use numPartitions variable, fix grammar.
c800798 [Michael Armbrust] Add build status icon.
0cf5a75 [Michael Armbrust] Merge pull request #16 from marmbrus/filterPushDown
05d3a0d [Michael Armbrust] Refactor to avoid serializing ordering details with every row.
f2fdd77 [Michael Armbrust] fix required distribtion for aggregate.
658866e [Michael Armbrust] Pull back in changes made by @yhuai eliminating CoGroupedLocallyRDD.scala
583a337 [Michael Armbrust] break apart distribution and partitioning.
e8d41a9 [Michael Armbrust] Merge remote-tracking branch 'yin/exchangeOperator' into exchangeOperator
0ff8be7 [Michael Armbrust] Cleanup spurious changes and fix doc links.
73c70de [Yin Huai] add a first set of unit tests for data properties.
fbfa437 [Michael Armbrust] Merge remote-tracking branch 'databricks/master' into filterPushDown Minor doc improvements.
2b9d80f [Yin Huai] initial commit of adding exchange operators to physical plans.
fcbc03b [Michael Armbrust] Fix if ().
7b9080c [Michael Armbrust] Create OrderedRow class to allow ordering to be used by multiple operators.
b4adb0f [Michael Armbrust] Merge pull request #14 from marmbrus/castingAndTypes
b2a1ec5 [Michael Armbrust] add comment on how using numeric implicitly complicates spark serialization.
e286d20 [Michael Armbrust] address code review comments.
80d0681 [Michael Armbrust] fix scaladoc links.
de0c248 [Michael Armbrust] Print the executed plan in SharkQuery toString.
3413e61 [Michael Armbrust] Add mapChildren and withNewChildren methods to TreeNode.
404d552 [Michael Armbrust] Better exception when unbound attributes make it to evaluation.
fb84ae4 [Michael Armbrust] Refactor DataProperty into Distribution.
2abb0bc [Michael Armbrust] better debug messages, use exists.
098dfc4 [Michael Armbrust] Implement Long sorting again.
60f3a9a [Michael Armbrust] More aggregate functions out of the aggregate class to make things more readable.
a1ef62e [Michael Armbrust] Print the executed plan in SharkQuery toString.
dfce426 [Michael Armbrust] Add mapChildren and withNewChildren methods to TreeNode.
037a2ed [Michael Armbrust] Better exception when unbound attributes make it to evaluation.
ec90620 [Michael Armbrust] Support for Sets as arguments to TreeNode classes.
b21f803 [Michael Armbrust] Merge pull request #11 from marmbrus/goldenGen
83adb9d [Yin Huai] add DataProperty
5a26292 [Michael Armbrust] Rules to bring casting more inline with Hive semantics.
f0e0161 [Michael Armbrust] Move numeric types into DataTypes simplifying evaluator.  This can probably also be use for codegen...
6d2924d [Michael Armbrust] add support for If. Not integrated in HiveQL yet.
ccc4dbf [Michael Armbrust] Add optimization rule to simplify casts.
058ec15 [Michael Armbrust] handle more writeables.
ffa9f25 [Michael Armbrust] blacklist some more MR tests.
aa2239c [Michael Armbrust] filter test lines containing Owner:
f71a325 [Michael Armbrust] Update golden jar.
a3003ae [Michael Armbrust] Update makefile to use better sharding support.
568d150 [Michael Armbrust] Updates to white/blacklist.
8351f25 [Michael Armbrust] Add an ignored test to remind us we don't do empty aggregations right.
c4104ec [Michael Armbrust] Numerous improvements to testing infrastructure.  See comments for details.
09c6300 [Michael Armbrust] Add nullability information to StructFields.
5460b2d [Michael Armbrust] load srcpart by default.
3695141 [Michael Armbrust] Lots of parser improvements.
965ac9a [Michael Armbrust] Add expressions that allow access into complex types.
3ba53c9 [Michael Armbrust] Output type suffixes on AttributeReferences.
8777489 [Michael Armbrust] Initial support for operators that allow the user to specify partitioning.
e57f97a [Michael Armbrust] more decimal/null support.
e1440ed [Michael Armbrust] Initial support for function specific type conversions.
1814ed3 [Michael Armbrust] use childrenResolved function.
f2ec57e [Michael Armbrust] Begin supporting decimal.
6924e6e [Michael Armbrust] Handle NullTypes when resolving HiveUDFs
7fcfa8a [Michael Armbrust] Initial support for parsing unspecified partition parameters.
d0124f3 [Michael Armbrust] Correctly type null literals.
b65626e [Michael Armbrust] Initial support for parsing BigDecimal.
a90efda [Michael Armbrust] utility function for outputing string stacktraces.
7102f33 [Michael Armbrust] methods with side-effects should use ().
3ccaef7 [Michael Armbrust] add renaming TODO.
bc282c7 [Michael Armbrust] fix bug in getNodeNumbered
c8e89d5 [Michael Armbrust] memoize inputSet calculation.
6aefa46 [Michael Armbrust] Skip folding literals.
a72e540 [Michael Armbrust] Add IN operator.
04f885b [Michael Armbrust] literals are only non-nullable if they are not null.
35d2948 [Michael Armbrust] correctly order partition and normal attributes in hive relation output.
12fd52d [Michael Armbrust] support for sorting longs.
0606520 [Michael Armbrust] drop old comment.
859200a [Michael Armbrust] support for reading more types from the metastore.
1fedd18 [Michael Armbrust] coercion from null to numeric types
71e902d [Michael Armbrust] fix test cases.
cc06b6c [Michael Armbrust] Merge remote-tracking branch 'databricks/master' into interviewAnswer
8a8b521 [Reynold Xin] Merge pull request #8 from marmbrus/testImprovment
86355a6 [Michael Armbrust] throw error if there are unexpected join clauses.
c5842d2 [Michael Armbrust] don't throw an error when a select clause outputs multiple copies of the same attribute.
0e975ea [Michael Armbrust] parse bucket sampling as percentage sampling
a92919d [Michael Armbrust] add alter view as to native commands
f58d5a5 [Michael Armbrust] support for parsing SELECT DISTINCT
f0faa26 [Michael Armbrust] add sample and distinct operators.
ef7b943 [Michael Armbrust] add metastore support for float
e9f4588 [Michael Armbrust] fix > 100 char.
755b229 [Michael Armbrust] blacklist some ddl tests.
9ae740a [Michael Armbrust] blacklist more tests that require MR.
4cfc11a [Michael Armbrust] more test coverage.
0d9d56a [Michael Armbrust] add more native commands to parser
78d730d [Michael Armbrust] Load src test table on RESET.
8364ec2 [Michael Armbrust] whitelist all possible partition values.
b01468d [Michael Armbrust] support path rewrites when the query begins with a comment.
4c6b454 [Michael Armbrust] add option for recomputing the cached golden answer when tests fail.
4c5fb0f [Michael Armbrust] makefile target for building new whitelist.
4b6fed8 [Michael Armbrust] support for parsing both DESTINATION and INSERT_INTO.
516481c [Michael Armbrust] Ignore requests to explain native commands.
68aa2e6 [Michael Armbrust] Stronger type for Token extractor.
ca4ea26 [Michael Armbrust] Support for parsing UDF(*).
1aafea3 [Michael Armbrust] Configure partition whitelist in TestShark reset.
9627616 [Michael Armbrust] Use current database as default database.
9b02b44 [Michael Armbrust] Fix spelling error. Add failFast mode.
6f64cee [Michael Armbrust] don't line wrap string literal
eafaeed [Michael Armbrust] add type documentation
f54c94c [Michael Armbrust] make golden answers file a test dependency
5362365 [Michael Armbrust] push conditions into join
0d2388b [Michael Armbrust] Point at databricks hosted scaladoc.
73b29cd [Michael Armbrust] fix bad casting
9aa06c5 [Michael Armbrust] Merge pull request #7 from marmbrus/docFixes
7eff191 [Michael Armbrust] link all the expression names.
83227e4 [Michael Armbrust] fix scaladoc list syntax, add docs for some rules
9de6b74 [Michael Armbrust] fix language feature and deprecation warnings.
0b1960a [Michael Armbrust] Fix broken scala doc links / warnings.
b1acb36 [Michael Armbrust] Merge pull request #3 from yhuai/evalauteLiteralsInExpressions
01c00c2 [Michael Armbrust] new golden
5c14857 [Yin Huai] Merge remote-tracking branch 'upstream/master' into evalauteLiteralsInExpressions
b749b51 [Michael Armbrust] Merge pull request #5 from marmbrus/testCaching
66adceb [Michael Armbrust] Merge pull request #6 from marmbrus/joinWork
1a393da [Yin Huai] folded -> foldable
1e964ea [Yin Huai] update
a43d41c [Michael Armbrust] more tests passing!
8ca38d0 [Michael Armbrust] begin support for varchar / binary types.
ab8bbd1 [Michael Armbrust] parsing % operator
c16c8b5 [Michael Armbrust] case insensitive checking for hooks in tests.
3a90a5f [Michael Armbrust] simpler output when running a single test from the commandline.
5332fee [Yin Huai] Merge remote-tracking branch 'upstream/master' into evalauteLiteralsInExpressions
367fb9e [Yin Huai] update
0cd5cc6 [Michael Armbrust] add BIGINT cast parsing
61b266f [Michael Armbrust] comment for eliminate subqueries.
d72a5a2 [Michael Armbrust] add long to literal factory object.
b3bd15f [Michael Armbrust] blacklist more mr requiring tests.
e06fd38 [Michael Armbrust] black list map reduce tests.
8e7ce30 [Michael Armbrust] blacklist some env specific tests.
6250cbd [Michael Armbrust] Do not exit on test failure
b22b220 [Michael Armbrust] also look for cached hive test answers on the classpath.
b6e4899 [Yin Huai] formatting
e75c90d [Reynold Xin] Merge pull request #4 from marmbrus/hive12
5fabbec [Michael Armbrust] ignore partitioned scan test. scan seems to be working but there is some error about the table already existing?
9e190f5 [Michael Armbrust] drop unneeded ()
68b58c1 [Michael Armbrust] drop a few more tests.
b0aa400 [Michael Armbrust] update whitelist.
c99012c [Michael Armbrust] skip tests with hooks
db00ebf [Michael Armbrust] more types for hive udfs
dbc3678 [Michael Armbrust] update ghpages repo
138f53d [Yin Huai] addressed comments and added a space after a space after the defining keyword of every control structure.
6f954ee [Michael Armbrust] export the hadoop classpath when starting sbt, required to invoke hive during tests.
46bf41b [Michael Armbrust] add a makefile for priming the test answer cache in parallel.  usage: "make -j 8 -i"
8d47ed4 [Yin Huai] comment
2795f05 [Yin Huai] comment
e003728 [Yin Huai] move OptimizerSuite to the package of catalyst.optimizer
2941d3a [Yin Huai] Merge remote-tracking branch 'upstream/master' into evalauteLiteralsInExpressions
0bd1688 [Yin Huai] update
6a7bd75 [Michael Armbrust] fix partition column delimiter configuration.
e942da1 [Michael Armbrust] Begin upgrade to Hive 0.12.0.
b8cd7e3 [Michael Armbrust] Merge pull request #7 from rxin/moreclean
52864da [Reynold Xin] Added executeCollect method to SharkPlan.
f0e1cbf [Reynold Xin] Added resolved lazy val to LogicalPlan.
b367e36 [Reynold Xin] Replaced the use of ??? with UnsupportedOperationException.
38124bd [Yin Huai] formatting
2924468 [Yin Huai] add two tests for testing pre-order and post-order tree traversal, respectively
555d839 [Reynold Xin] More cleaning ...
d48d0e1 [Reynold Xin] Code review feedback.
aa2e694 [Yin Huai] Merge remote-tracking branch 'upstream/master' into evalauteLiteralsInExpressions
5c421ac [Reynold Xin] Imported SharkEnv, SharkContext, and HadoopTableReader to remove Shark dependency.
479e055 [Reynold Xin] A set of minor changes, including: - import order - limit some lines to 100 character wide - inline code comment - more scaladocs - minor spacing (i.e. add a space after if)
da16e45 [Reynold Xin] Merge pull request #3 from rxin/packagename
e36caf5 [Reynold Xin] Renamed Rule.name to Rule.ruleName since name is used too frequently in the code base and is shadowed often by local scope.
72426ed [Reynold Xin] Rename shark2 package to execution.
0892153 [Reynold Xin] Merge pull request #2 from rxin/packagename
e58304a [Reynold Xin] Merge pull request #1 from rxin/gitignore
3f9fee1 [Michael Armbrust] rewrite push filter through join optimization.
c6527f5 [Reynold Xin] Moved the test src files into the catalyst directory.
c9777d8 [Reynold Xin] Put all source files in a catalyst directory.
019ea74 [Reynold Xin] Updated .gitignore to include IntelliJ files.
80ca4be [Timothy Chen] Address comments
0079392 [Michael Armbrust] support for multiple insert commands in a single query
75b5a01 [Michael Armbrust] remove space.
4283400 [Timothy Chen] Add limited predicate push down
e547e50 [Michael Armbrust] implement First.
e77c9b6 [Michael Armbrust] more work on unique join.
c795e06 [Michael Armbrust] improve star expansion
a26494e [Michael Armbrust] allow aliases to have qualifiers
d078333 [Michael Armbrust] remove extra space
a75c023 [Michael Armbrust] implement Coalesce
3a018b6 [Michael Armbrust] fix up docs.
ab6f67d [Michael Armbrust] import the string "null" as actual null.
5377c04 [Michael Armbrust] don't call dataType until checking if children are resolved.
191ce3e [Michael Armbrust] analyze rewrite test query.
60b1526 [Michael Armbrust] don't call dataType until checking if children are resolved.
2ab5a32 [Michael Armbrust] stop using uberjar as it has its own set of issues.
e42f75a [Michael Armbrust] Merge remote-tracking branch 'origin/master' into HEAD
c086a35 [Michael Armbrust] docs, spacing
c4060e4 [Michael Armbrust] cleanup
3b85462 [Michael Armbrust] more tests passing
bcfc8c5 [Michael Armbrust] start supporting partition attributes when inserting data.
c944a95 [Michael Armbrust] First aggregate expression.
1e28311 [Michael Armbrust] make tests execute in alpha order again
a287481 [Michael Armbrust] spelling
8492548 [Michael Armbrust] beginning of UNIQUEJOIN parsing.
a6ab6c7 [Michael Armbrust] add !=
4529594 [Michael Armbrust] draft of coalesce
70f253f [Michael Armbrust] more tests passing!
7349e7b [Michael Armbrust] initial support for test thrift table
d3c9305 [Michael Armbrust] fix > 100 char line
93b64b0 [Michael Armbrust] load test tables that are args to "DESCRIBE"
06b2aba [Michael Armbrust] don't be case sensitive when fixing load paths
6355d0e [Michael Armbrust] match actual return type of count with expected
cda43ab [Michael Armbrust] don't throw an exception when one of the join tables is empty.
fd4b096 [Michael Armbrust] fix casing of null strings as well.
4632695 [Michael Armbrust] support for megastore bigint
67b88cf [Michael Armbrust] more verbose debugging of evaluation return types
c680e0d [Michael Armbrust] Failed string => number conversion should return null.
2326be1 [Michael Armbrust] make getClauses case insensitive.
dac2786 [Michael Armbrust] correctly handle null values when going from string to numeric types.
045ac4b [Yin Huai] Merge remote-tracking branch 'upstream/master' into evalauteLiteralsInExpressions
fb5ddfd [Michael Armbrust] move ViewExamples to examples/
83833e8 [Michael Armbrust] more tests passing!
47c98d6 [Michael Armbrust] add query tests for like and hash.
1724c16 [Michael Armbrust] clear lines that contain last updated times.
cfd6bbc [Michael Armbrust] Quick skipping of tests that we can't even parse.
9b2642b [Michael Armbrust] make the blacklist support regexes
1d50af6 [Michael Armbrust] more datatypes, fix nonserializable instance variables in udfs
910e33e [Michael Armbrust] basic support for building an assembly jar.
d55bb52 [Michael Armbrust] add local warehouse/metastore to gitignore.
495d9dc [Michael Armbrust] Add an expression for when we decide to support LIKE natively instead of using the HIVE udf.
65f4e69 [Michael Armbrust] remove incorrect comments
0831a3c [Michael Armbrust] support for parsing some operator udfs.
6c27aa7 [Michael Armbrust] more cast parsing.
43db061 [Michael Armbrust] significant generalization of hive udf functionality.
3fe24ec [Michael Armbrust] better implementation of 3vl in Evaluate, fix some > 100 char lines.
e5690a6 [Michael Armbrust] add BinaryType
adab892 [Michael Armbrust] Clear out functions that are created during tests when reset is called.
d408021 [Michael Armbrust] support for printing out arrays in the output in the same form as hive (e.g., [e1, e1]).
8d5f504 [Michael Armbrust] Example of schema RDD using scala's dynamic trait, resulting in a more standard ORM style of usage.
21f0d91 [Michael Armbrust] Simple example of schemaRdd with scala filter function.
0daaa0e [Michael Armbrust] Promote booleans that appear in comparisons.
2b70abf [Michael Armbrust] true and false literals.
ef8b0a5 [Michael Armbrust] more tests.
14d070f [Michael Armbrust] add support for correctly extracting partition keys.
0afbe73 [Yin Huai] Merge remote-tracking branch 'upstream/master' into evalauteLiteralsInExpressions
69a0bd4 [Michael Armbrust] promote strings in predicates with number too.
3946e31 [Michael Armbrust] don't build strings unless assertion fails.
90c453d [Michael Armbrust] more tests passing!
6e6417a [Michael Armbrust] correct handling of nulls in boolean logic and sorting.
8000504 [Michael Armbrust] Improve type coercion.
9087152 [Michael Armbrust] fix toString of Not.
58b111c [Michael Armbrust] fix bad scaladoc tag.
d5c05c6 [Michael Armbrust] For now, ignore the big data benchmark tests when the data isn't there.
ac6376d [Michael Armbrust] Split out general shark query execution driver from test harness.
1d0ae1e [Michael Armbrust] Switch from IndexSeq[Any] to Row interface that will allow us unboxed access to primitive types.
d873b2b [Yin Huai] Remove numbers associated with test cases.
8545675 [Yin Huai] Merge remote-tracking branch 'upstream/master' into evalauteLiteralsInExpressions
b34a9eb [Michael Armbrust] Merge branch 'master' into filterPushDown
d1e7b8e [Michael Armbrust] Update README.md
c8b1553 [Michael Armbrust] Update README.md
9307ef9 [Michael Armbrust] update list of passing tests.
934c18c [Michael Armbrust] Filter out non-deterministic lines when comparing test answers.
a045c9c [Michael Armbrust] SparkAggregate doesn't actually support sum right now.
ae0024a [Yin Huai] update
cf80545 [Yin Huai] Merge remote-tracking branch 'origin/evalauteLiteralsInExpressions' into evalauteLiteralsInExpressions
21976ae [Yin Huai] update
b4999fe [Yin Huai] Merge remote-tracking branch 'upstream/filterPushDown' into evalauteLiteralsInExpressions
dedbf0c [Yin Huai] support Boolean literals
eaac9e2 [Yin Huai] explain the limitation of the current EvaluateLiterals
37817b5 [Yin Huai] add a comment to EvaluateLiterals.
468667f [Yin Huai] First draft of literal evaluation in the optimization phase. TreeNode has been extended to support transform in the post order. So, for an expression, we can evaluate literal from the leaf nodes of this expression tree. For an attribute reference in the expression node, we just leave it as is.
b1d1843 [Michael Armbrust] more work on big data benchmark tests.
cc9a957 [Michael Armbrust] support for creating test tables outside of TestShark
7d7fa9f [Michael Armbrust] support for create table as
5f54f03 [Michael Armbrust] parsing for ASC
d42b725 [Michael Armbrust] Sum of strings requires cast
34b30fa [Michael Armbrust] not all attributes need to be bound (e.g. output attributes that are contained in non-leaf operators.)
81659cb [Michael Armbrust] implement transform operator.
5cd76d6 [Michael Armbrust] break up the file based test case code for reuse
1031b65 [Michael Armbrust] support for case insensitive resolution.
320df04 [Michael Armbrust] add snapshot repo for databricks (has shark/spark snapshots)
b6f083e [Michael Armbrust] support for publishing scala doc to github from sbt
d9d18b4 [Michael Armbrust] debug logging implicit.
669089c [Yin Huai] support Boolean literals
ef3321e [Yin Huai] explain the limitation of the current EvaluateLiterals
73a05fd [Yin Huai] add a comment to EvaluateLiterals.
191eb7d [Yin Huai] First draft of literal evaluation in the optimization phase. TreeNode has been extended to support transform in the post order. So, for an expression, we can evaluate literal from the leaf nodes of this expression tree. For an attribute reference in the expression node, we just leave it as is.
80039cc [Yin Huai] Merge pull request #1 from yhuai/master
cbe1ca1 [Yin Huai] add explicit result type to the overloaded sideBySide
5c518e4 [Michael Armbrust] fix bug in test.
b50dd0e [Michael Armbrust] fix return type of overloaded method
05679b7 [Michael Armbrust] download assembly jar for easy compiling during interview.
8c60cc0 [Michael Armbrust] Update README.md
03b9526 [Michael Armbrust] First draft of optimizer tests.
f392755 [Michael Armbrust] Add flatMap to TreeNode
6cbe8d1 [Michael Armbrust] fix bug in side by side, add support for working with unsplit strings
15a53fc [Michael Armbrust] more generic sum calculation and better binding of grouping expressions.
06749d0 [Michael Armbrust] add expression enumerations for query plan operators and recursive version of transform expression.
4b0a888 [Michael Armbrust] implement string comparison and more casts.
356b321 [Michael Armbrust] Update README.md
3776395 [Michael Armbrust] Update README.md
304d17d [Michael Armbrust] Create README.md
b7d8be0 [Michael Armbrust] more tests passing.
b82481f [Michael Armbrust] add todo comment.
02e6dee [Michael Armbrust] add another test that breaks the harness to the blacklist.
cc5efe3 [Michael Armbrust] First draft of broadcast nested loop join with full outer support.
c43a259 [Michael Armbrust] comments
15ff448 [Michael Armbrust] better error message when a dsl test throws an exception
76ec650 [Michael Armbrust] fix join conditions
e10df99 [Michael Armbrust] Create new expr ids for local relations that exist more than once in a query plan.
91573a4 [Michael Armbrust] initial type promotion
e2ef4a5 [Michael Armbrust] logging
e43dc1e [Michael Armbrust] add string => int cast evaluation
f1f7e96 [Michael Armbrust] fix incorrect generation of join keys
2b27230 [Michael Armbrust] add depth based subtree access
0f6279f [Michael Armbrust] broken tests.
389bc0b [Michael Armbrust] support for partitioned columns in output.
12584f4 [Michael Armbrust] better errors for missing clauses. support for matching multiple clauses with the same name.
b67a225 [Michael Armbrust] better errors when types don't match up.
9e74808 [Michael Armbrust] add children resolved.
6d03ce9 [Michael Armbrust] defaults for unresolved relation
2469b00 [Michael Armbrust] skip nodes with unresolved children when doing coersions
be5ae2c [Michael Armbrust] better resolution logging
cb7b5af [Michael Armbrust] views example
420e05b [Michael Armbrust] more tests passing!
6916c63 [Michael Armbrust] Reading from partitioned hive tables.
a1245f9 [Michael Armbrust] more tests passing
956e760 [Michael Armbrust] extended explain
5f14c35 [Michael Armbrust] more test tables supported
175c43e [Michael Armbrust] better errors for parse exceptions
480ade5 [Michael Armbrust] don't use partial cached results.
8a9d21c [Michael Armbrust] fix evaluation
7aee69c [Michael Armbrust] parsing for joins, boolean logic
7fcf480 [Michael Armbrust] test for and logic
3ea9b00 [Michael Armbrust] don't use simpleString if there are no new lines.
6902490 [Michael Armbrust] fix boolean logic evaluation
4d5eba7 [Michael Armbrust] add more dsl for expression arithmetic and boolean logic
8b2a2ee [Michael Armbrust] more tests passing!
ad1f3b4 [Michael Armbrust] toString for null literals
a5c0a1b [Michael Armbrust] more test harness improvements: * regex whitelist * side by side answer comparison (still needs formatting work)
60ec19d [Michael Armbrust] initial support for udfs
c45b440 [Michael Armbrust] support for is (not) null and boolean logic
7f4a1dc [Michael Armbrust] add NoRelation logical operator
72e183b [Michael Armbrust] support for null values in tree node args.
ad596d2 [Michael Armbrust] add sc to Union's otherCopyArgs
e5c9d1a [Michael Armbrust] use nonEmpty
dcc4fe1 [Michael Armbrust] support for src1 test table.
c78b587 [Michael Armbrust] casting.
75c3f3f [Michael Armbrust] add support for logging with scalalogging.
da2c011 [Michael Armbrust] make it more obvious when results are being truncated.
96b73ba [Michael Armbrust] more docs in TestShark
18524fd [Michael Armbrust] add method to SharkSqlQuery for directly executing the same query on hive.
e6d063b [Michael Armbrust] more join tests.
664c1c3 [Michael Armbrust] make parsing of function names case insensitive.
0967d4e [Michael Armbrust] fix hardcoded path to hiveDevHome.
1a6db68 [Michael Armbrust] spelling
7638cb4 [Michael Armbrust] simple join execution with dsl tests.  no hive tests yes.
859d4c9 [Michael Armbrust] better argString printing of nested trees.
fc53615 [Michael Armbrust] add same instance comparisons for tree nodes.
a026e6b [Michael Armbrust] move out hive specific operators
fff4d1c [Michael Armbrust] add simple query execution debugging
e2120ab [Michael Armbrust] sorting for strings
da06eb6 [Michael Armbrust] Parsing for sortby and joins
9eb5c5e [Michael Armbrust] override equality in Attribute references to compare exprId.
8eb2460 [Michael Armbrust] add system property to override whitelist.
88124bb [Michael Armbrust] make strategy evaluation lazy.
74a3a21 [Michael Armbrust] implement outputSet
d25b171 [Michael Armbrust] Add AND and OR expressions
67f0a4a [Michael Armbrust] dsl improvements: string to attribute, subquery, unionAll
12acf0a [Michael Armbrust] add .DS_Store for macs
f7da6ce [Michael Armbrust] add agg with grouping expr in select test
36805b3 [Michael Armbrust] pull out and improve aggregation
75613e1 [Michael Armbrust] better evaluations failure messages.
4789a35 [Michael Armbrust] weaken type since its hard to create pure references.
e89dd36 [Michael Armbrust] no newline for online trees
d0590d4 [Michael Armbrust] include stack trace for catalyst failures.
081c0d9 [Michael Armbrust] more generic computation of agg functions.
31af3a0 [Michael Armbrust] fail when clauses are unhandeled in the parser
ecd45b2 [Michael Armbrust] Add more passing tests.
97d5419 [Michael Armbrust] fix alignment.
565cc13 [Michael Armbrust] make the canary query optional.
a95e65c [Michael Armbrust] support for resolving qualified attribute references.
e1dfa0c [Michael Armbrust] better error reporting for comparison tests when hive works but catalyst fails.
4640a0b [Michael Armbrust] handle test tables when database is specified.
bef12e3 [Michael Armbrust] Add Subquery node and trivial optimizer to remove it after analysis.
fec5158 [Michael Armbrust] add hive / idea files to .gitignore
3f97ffe [Michael Armbrust] Rename Hive => HiveQl
656b836 [Michael Armbrust] Support for parsing select clause aliases.
3ca7414 [Michael Armbrust] StopAfter needs otherCopyArgs.
3ffde66 [Michael Armbrust] When the child of an alias is unresolved it should return an unresolved attribute instead of throwing an exception.
8cbef8a [Michael Armbrust] spelling
aa8c37c [Michael Armbrust] Better toString for SortOrder
1bb8b45 [Michael Armbrust] fix error message for UnresolvedExceptions
a2e0327 [Michael Armbrust] add a bunch of tests.
4a3e1ea [Michael Armbrust] docs and use shark for data loading.
339bb8f [Michael Armbrust] better docs, Not support
1d7b2d9 [Michael Armbrust] Add NaN conversions.
46a2534 [Michael Armbrust] only run canary query on failure.
8996066 [Michael Armbrust] remove protected from makeCopy
53bcf41 [Michael Armbrust] testing improvements: * reset hive vars * delete indexes and tables * delete database * reset to use default database * record tests that pass
04a372a [Michael Armbrust] add a flag for running all tests.
3b2235b [Michael Armbrust] More general implementation of arithmetic.
edd7795 [Michael Armbrust] More testing improvements: * Check that results match for native commands * Ensure explain commands can be planned * Cache hive "golden" results
da6c577 [Michael Armbrust] add string <==> file utility functions.
3adf5ca [Michael Armbrust] Initial support for groupBy and count.
7bcd8a4 [Michael Armbrust] Improvements to comparison tests: * Sort answer when query doesn't contain an order by. * Display null values the same as Hive. * Print full query results in easy to read format when they differ.
a52e7c9 [Michael Armbrust] Transform children that are present in sequences of the product.
d66ba7e [Michael Armbrust] drop printlns.
88f2efd [Michael Armbrust] Add sum / count distinct expressions.
05adedc [Michael Armbrust] rewrite relative paths when loading data in TestShark
07784b3 [Michael Armbrust] add support for rewriting paths and running 'set' commands.
b8a9910 [Michael Armbrust] quote tests passing.
8e5e267 [Michael Armbrust] handle aliased select expressions.
4286a96 [Michael Armbrust] drop debugging println
ac34aeb [Michael Armbrust] proof of concept for hive ast transformations.
2238b00 [Michael Armbrust] better error when makeCopy functions fails due to incorrect arguments
ff1eab8 [Michael Armbrust] start trying to make insert into hive table more general.
74a6337 [Michael Armbrust] use fastEquals when doing transformations.
1184a23 [Michael Armbrust] add native test for escapes.
b972b18 [Michael Armbrust] create BaseRelation class
fa6bce9 [Michael Armbrust] implement union
6391a87 [Michael Armbrust] count aggregate.
d47c317 [Michael Armbrust] add unary minus, more tests passing.
c7114e4 [Michael Armbrust] first draft of star expansion.
044c43d [Michael Armbrust] better support for numeric literal parsing.
1d0f072 [Michael Armbrust] use native drop table as it doesn't appear to fail when the "table" is actually a view.
61503c5 [Michael Armbrust] add cached toRdd
2036883 [Michael Armbrust] skip explain queries when testing.
ebac4b1 [Michael Armbrust] fix bug in sort reference calculation
ca0dee0 [Michael Armbrust] docs.
1ee0471 [Michael Armbrust] string literal parsing.
357278b [Michael Armbrust] add limit support
9b3e479 [Michael Armbrust] creation of string literals.
02efa30 [Michael Armbrust] alias evaluation
cb68b33 [Michael Armbrust] parsing for random sample in hive ql.
126dd36 [Michael Armbrust] include query plans in failure output
bb59ae9 [Michael Armbrust] doc fixes
7e68286 [Michael Armbrust] fix confusing naming
768bb25 [Michael Armbrust] handle errors in shark query toString
829c3ce [Michael Armbrust] Auto loading of test data on demand. Add reset method to test shark.  Make test shark a singleton to avoid weirdness with the hive megastore.
ad02e41 [Michael Armbrust] comment jdo dependency
7bc89fe [Michael Armbrust] add collect to TreeNode.
438cf74 [Michael Armbrust] create explicit treeString function in addition to toString override. docs.
09679ee [Michael Armbrust] fix bug in TreeNode foreach
2930b27 [Michael Armbrust] more specific name for del query tests.
8842549 [Michael Armbrust] docs.
da81f81 [Michael Armbrust] Implementation and tests for simple AVG query in Hive SQL.
a8969b9 [Michael Armbrust] Factor out hive query comparison test framework.
1a7efb0 [Michael Armbrust] specialize spark aggregate for global aggregations.
a36dd9a [Michael Armbrust] evaluation for other > data types.
cae729b [Michael Armbrust] remove unnecessary lazy vals.
d8e12af [Michael Armbrust] docs
3a60d67 [Michael Armbrust] implement average, placeholder for count
f05c106 [Michael Armbrust] checkAnswer handles single row results.
2730534 [Michael Armbrust] implement inputSet
a9aa79d [Michael Armbrust] debugging for sort exec
8bec3c9 [Michael Armbrust] better tree makeCopy when there are two constructors.
554b4b2 [Michael Armbrust] BoundAttribute pretty printing.
754f5fa [Michael Armbrust] dsl for setting nullability
a206d7a [Michael Armbrust] clean up query tests.
84ad6ef [Michael Armbrust] better sort implementation and tests.
de24923 [Michael Armbrust] add double type.
9611a2c [Michael Armbrust] literal creation for doubles.
7358313 [Michael Armbrust] sort order returns child type.
b544715 [Michael Armbrust] implement eval for rand, and > for doubles
7013bad [Michael Armbrust] asc, desc should work for expressions and unresolved attributes (symbols)
1c1a35e [Michael Armbrust] add simple Rand expression.
3ca51de [Michael Armbrust] add orderBy to dsl
7ae41ab [Michael Armbrust] more literal implicit conversions
b18b675 [Michael Armbrust] First cut at native query tests for shark.
d392e29 [Michael Armbrust] add toRdd implicit conversion for logical plans in TestShark.
5eac895 [Michael Armbrust] better error when descending is specified.
2b16f86 [Michael Armbrust] add todo
e527bb8 [Michael Armbrust] remove arguments to binary predicate constructor as they seem to break serialization
9dde3c8 [Michael Armbrust] add project and filter operations.
ad9037b [Michael Armbrust] Add support for local relations.
6227143 [Michael Armbrust] evaluation of Equals.
7526290 [Michael Armbrust] BoundReference should also be an Attribute.
bd33e26 [Michael Armbrust] more documentation
5de0ea3 [Michael Armbrust] Move all shark specific into a separate package.  Lots of documentation improvements.
0ae292b [Michael Armbrust] implement calculation of sort expressions.
9fd5011 [Michael Armbrust] First cut at expression evaluation.
6259e3a [Michael Armbrust] cleanup
787e5a2 [Michael Armbrust] use fastEquals
f90da36 [Michael Armbrust] better printing of optimization exceptions
b05dd67 [Michael Armbrust] Application of rules to fixed point.
bb2e0db [Michael Armbrust] pretty print for literals.
1ec3287 [Michael Armbrust] Add extractor for IntegerLiterals.
d3a3687 [Michael Armbrust] add fastEquals
2b4935b [Michael Armbrust] set sbt.version explicitly
46dfd7f [Michael Armbrust] first cut at checking answer for HiveCompatability tests.
c79f2fd [Michael Armbrust] insert operator should return an empty rdd.
14c22ec [Michael Armbrust] implement sorting when the sort expression is the first attribute of the input.
ae7b4c3 [Michael Armbrust] remove implicit dependencies.  now compiles without copying things into lib/ manually.
84082f9 [Michael Armbrust] add sbt binaries and scripts
15371a8 [Michael Armbrust] First draft of simple Hive DDL parser.
063bf44 [Michael Armbrust] Periods should end all comments.
e1f7f4c [Michael Armbrust] Remove "NativePlaceholder" hack.
ed3633e [Michael Armbrust] start consolidating Hive/Shark specific code. first hive compatibility test case passing!
b34a770 [Michael Armbrust] Add data sink strategy, make strategy application a little more robust.
e7174ec [Michael Armbrust] fix schema, add docs, make helper method protected.
26f410a [Michael Armbrust] physical traits should extend PhysicalPlan.
dc72469 [Michael Armbrust] beginning of hive compatibility testing framework.
0763490 [Michael Armbrust] support for hive native command pass-through.
d8a924f [Michael Armbrust] scaladoc
29a7163 [Michael Armbrust] Insert into hive table physical operator.
633cebc [Michael Armbrust] better error message when there is no appropriate planning strategy.
59ac444 [Michael Armbrust] add unary expression
3aa1b28 [Michael Armbrust] support for table names in the form 'database.tableName'
665f7d0 [Michael Armbrust] add logical nodes for hive data sinks.
64d2923 [Michael Armbrust] Add classes for representing sorts.
f72b7ce [Michael Armbrust] first trivial end to end query execution.
5c7d244 [Michael Armbrust] first draft of references implementation.
7bff274 [Michael Armbrust] point at new shark.
c7cd57f [Michael Armbrust] docs for util function.
910811c [Michael Armbrust] check each item of the sequence
ef21a0b [Michael Armbrust] line up comments.
4b765d5 [Michael Armbrust] docs, drop println
6f9bafd [Michael Armbrust] empty output for unresolved relation to avoid exception in resolution.
a703c49 [Michael Armbrust] this order works better until fixed point is implemented.
ec1d7c0 [Michael Armbrust] Simple attribute resolution.
069df02 [Michael Armbrust] parsing binary predicates
a1cf754 [Michael Armbrust] add joins and equality.
3f5bc98 [Michael Armbrust] add optiq to sbt.
54f3460 [Michael Armbrust] initial optiq parsing.
d9161ce [Michael Armbrust] add join operator
1e423eb [Michael Armbrust] placeholders in LogicalPlan, docs
24ef6fb [Michael Armbrust] toString for alias.
ae7d776 [Michael Armbrust] add nullability changing function
d49dc02 [Michael Armbrust] scaladoc for named exprs
7c45dd7 [Michael Armbrust] pretty printing of trees.
78e34bf [Michael Armbrust] simple git ignore.
7ba19be [Michael Armbrust] First draft of interface to hive metastore.
7e7acf0 [Michael Armbrust] physical placeholder.
1c11136 [Michael Armbrust] first draft of error handling / plans for debugging.
3766a41 [Michael Armbrust] rearrange utility functions.
7fb3d5e [Michael Armbrust] docs and equality improvements.
45da47b [Michael Armbrust] flesh out plans and expressions a little. first cut at named expressions.
002d4d4 [Michael Armbrust] default to no alias.
be25003 [Michael Armbrust] add repl initialization to sbt.
0608a00 [Michael Armbrust] tighten public interface
a1a8b38 [Michael Armbrust] test that ids don't change for no-op transforms.
daa71ca [Michael Armbrust] foreach, maps, and scaladoc
6a158cb [Michael Armbrust] simple transform working.
db0299f [Michael Armbrust] basic analysis of relations minus transform function.
f74c4ee [Michael Armbrust] parsing a simple query.
08e4f57 [Michael Armbrust] upgrade scala include shark.
d3c6404 [Michael Armbrust] initial commit

62 files changed, 6538 insertions, 0 deletions

diff --git a/sql/catalyst/pom.xml b/sql/catalyst/pom.xml
new file mode 100644
index 0000000000..740f1fdc83
--- /dev/null
+++ b/sql/catalyst/pom.xml
@@ -0,0 +1,66 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ Licensed to the Apache Software Foundation (ASF) under one or more
+  ~ contributor license agreements.  See the NOTICE file distributed with
+  ~ this work for additional information regarding copyright ownership.
+  ~ The ASF licenses this file to You under the Apache License, Version 2.0
+  ~ (the "License"); you may not use this file except in compliance with
+  ~ the License.  You may obtain a copy of the License at
+  ~
+  ~    http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>org.apache.spark</groupId>
+        <artifactId>spark-parent</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+        <relativePath>../../pom.xml</relativePath>
+    </parent>
+
+    <groupId>org.apache.spark</groupId>
+    <artifactId>spark-catalyst_2.10</artifactId>
+    <packaging>jar</packaging>
+    <name>Spark Project Catalyst</name>
+    <url>http://spark.apache.org/</url>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.spark</groupId>
+            <artifactId>spark-core_${scala.binary.version}</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.typesafe</groupId>
+            <artifactId>scalalogging-slf4j_${scala.binary.version}</artifactId>
+            <version>1.0.1</version>
+        </dependency>
+        <dependency>
+            <groupId>org.scalatest</groupId>
+            <artifactId>scalatest_${scala.binary.version}</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.scalacheck</groupId>
+            <artifactId>scalacheck_${scala.binary.version}</artifactId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+    <build>
+        <outputDirectory>target/scala-${scala.binary.version}/classes</outputDirectory>
+        <testOutputDirectory>target/scala-${scala.binary.version}/test-classes</testOutputDirectory>
+        <plugins>
+            <plugin>
+                <groupId>org.scalatest</groupId>
+                <artifactId>scalatest-maven-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+</project>
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/SqlParser.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/SqlParser.scala
new file mode 100644
index 0000000000..d3b1070a58
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/SqlParser.scala
@@ -0,0 +1,328 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql.catalyst
+
+import scala.util.matching.Regex
+import scala.util.parsing.combinator._
+import scala.util.parsing.input.CharArrayReader.EofCh
+import lexical._
+import syntactical._
+import token._
+
+import analysis._
+import expressions._
+import plans._
+import plans.logical._
+import types._
+
+/**
+ * A very simple SQL parser.  Based loosly on:
+ * https://github.com/stephentu/scala-sql-parser/blob/master/src/main/scala/parser.scala
+ *
+ * Limitations:
+ *  - Only supports a very limited subset of SQL.
+ *  - Keywords must be capital.
+ *
+ * This is currently included mostly for illustrative purposes.  Users wanting more complete support
+ * for a SQL like language should checkout the HiveQL support in the sql/hive subproject.
+ */
+class SqlParser extends StandardTokenParsers {
+
+  def apply(input: String): LogicalPlan = {
+    phrase(query)(new lexical.Scanner(input)) match {
+      case Success(r, x) => r
+      case x => sys.error(x.toString)
+    }
+  }
+
+  protected case class Keyword(str: String)
+  protected implicit def asParser(k: Keyword): Parser[String] = k.str
+
+  protected class SqlLexical extends StdLexical {
+    case class FloatLit(chars: String) extends Token {
+      override def toString = chars
+    }
+    override lazy val token: Parser[Token] = (
+        identChar ~ rep( identChar | digit ) ^^
+          { case first ~ rest => processIdent(first :: rest mkString "") }
+      | rep1(digit) ~ opt('.' ~> rep(digit)) ^^ {
+        case i ~ None    => NumericLit(i mkString "")
+        case i ~ Some(d) => FloatLit(i.mkString("") + "." + d.mkString(""))
+      }
+      | '\'' ~ rep( chrExcept('\'', '\n', EofCh) ) ~ '\'' ^^
+        { case '\'' ~ chars ~ '\'' => StringLit(chars mkString "") }
+      | '\"' ~ rep( chrExcept('\"', '\n', EofCh) ) ~ '\"' ^^
+        { case '\"' ~ chars ~ '\"' => StringLit(chars mkString "") }
+      | EofCh ^^^ EOF
+      | '\'' ~> failure("unclosed string literal")
+      | '\"' ~> failure("unclosed string literal")
+      | delim
+      | failure("illegal character")
+    )
+
+    override def identChar = letter | elem('.') | elem('_')
+
+    override def whitespace: Parser[Any] = rep(
+      whitespaceChar
+    | '/' ~ '*' ~ comment
+    | '/' ~ '/' ~ rep( chrExcept(EofCh, '\n') )
+    | '#' ~ rep( chrExcept(EofCh, '\n') )
+    | '-' ~ '-' ~ rep( chrExcept(EofCh, '\n') )
+    | '/' ~ '*' ~ failure("unclosed comment")
+    )
+  }
+
+  override val lexical = new SqlLexical
+
+  protected val ALL = Keyword("ALL")
+  protected val AND = Keyword("AND")
+  protected val AS = Keyword("AS")
+  protected val ASC = Keyword("ASC")
+  protected val AVG = Keyword("AVG")
+  protected val BY = Keyword("BY")
+  protected val CAST = Keyword("CAST")
+  protected val COUNT = Keyword("COUNT")
+  protected val DESC = Keyword("DESC")
+  protected val DISTINCT = Keyword("DISTINCT")
+  protected val FALSE = Keyword("FALSE")
+  protected val FIRST = Keyword("FIRST")
+  protected val FROM = Keyword("FROM")
+  protected val FULL = Keyword("FULL")
+  protected val GROUP = Keyword("GROUP")
+  protected val HAVING = Keyword("HAVING")
+  protected val IF = Keyword("IF")
+  protected val IN = Keyword("IN")
+  protected val INNER = Keyword("INNER")
+  protected val IS = Keyword("IS")
+  protected val JOIN = Keyword("JOIN")
+  protected val LEFT = Keyword("LEFT")
+  protected val LIMIT = Keyword("LIMIT")
+  protected val NOT = Keyword("NOT")
+  protected val NULL = Keyword("NULL")
+  protected val ON = Keyword("ON")
+  protected val OR = Keyword("OR")
+  protected val ORDER = Keyword("ORDER")
+  protected val OUTER = Keyword("OUTER")
+  protected val RIGHT = Keyword("RIGHT")
+  protected val SELECT = Keyword("SELECT")
+  protected val STRING = Keyword("STRING")
+  protected val SUM = Keyword("SUM")
+  protected val TRUE = Keyword("TRUE")
+  protected val UNION = Keyword("UNION")
+  protected val WHERE = Keyword("WHERE")
+
+  // Use reflection to find the reserved words defined in this class.
+  protected val reservedWords =
+    this.getClass
+      .getMethods
+      .filter(_.getReturnType == classOf[Keyword])
+      .map(_.invoke(this).asInstanceOf[Keyword])
+
+  lexical.reserved ++= reservedWords.map(_.str)
+
+  lexical.delimiters += (
+    "@", "*", "+", "-", "<", "=", "<>", "!=", "<=", ">=", ">", "/", "(", ")",
+    ",", ";", "%", "{", "}", ":"
+  )
+
+  protected def assignAliases(exprs: Seq[Expression]): Seq[NamedExpression] = {
+    exprs.zipWithIndex.map {
+      case (ne: NamedExpression, _) => ne
+      case (e, i) => Alias(e, s"c$i")()
+    }
+  }
+
+  protected lazy val query: Parser[LogicalPlan] =
+    select * (
+      UNION ~ ALL ^^^ { (q1: LogicalPlan, q2: LogicalPlan) => Union(q1, q2) } |
+      UNION ~ opt(DISTINCT) ^^^ { (q1: LogicalPlan, q2: LogicalPlan) => Distinct(Union(q1, q2)) }
+    )
+
+  protected lazy val select: Parser[LogicalPlan] =
+    SELECT ~> opt(DISTINCT) ~ projections ~
+    opt(from) ~ opt(filter) ~
+    opt(grouping) ~
+    opt(having) ~
+    opt(orderBy) ~
+    opt(limit) <~ opt(";") ^^ {
+      case d ~ p ~ r ~ f ~ g ~ h ~ o ~ l  =>
+        val base = r.getOrElse(NoRelation)
+        val withFilter = f.map(f => Filter(f, base)).getOrElse(base)
+        val withProjection =
+          g.map {g =>
+            Aggregate(assignAliases(g), assignAliases(p), withFilter)
+          }.getOrElse(Project(assignAliases(p), withFilter))
+        val withDistinct = d.map(_ => Distinct(withProjection)).getOrElse(withProjection)
+        val withHaving = h.map(h => Filter(h, withDistinct)).getOrElse(withDistinct)
+        val withOrder = o.map(o => Sort(o, withHaving)).getOrElse(withHaving)
+        val withLimit = l.map { l => StopAfter(l, withOrder) }.getOrElse(withOrder)
+        withLimit
+  }
+
+  protected lazy val projections: Parser[Seq[Expression]] = repsep(projection, ",")
+
+  protected lazy val projection: Parser[Expression] =
+    expression ~ (opt(AS) ~> opt(ident)) ^^ {
+      case e ~ None => e
+      case e ~ Some(a) => Alias(e, a)()
+    }
+
+  protected lazy val from: Parser[LogicalPlan] = FROM ~> relations
+
+  // Based very loosly on the MySQL Grammar.
+  // http://dev.mysql.com/doc/refman/5.0/en/join.html
+  protected lazy val relations: Parser[LogicalPlan] =
+    relation ~ "," ~ relation ^^ { case r1 ~ _ ~ r2 => Join(r1, r2, Inner, None) } |
+    relation
+
+  protected lazy val relation: Parser[LogicalPlan] =
+    joinedRelation |
+    relationFactor
+
+  protected lazy val relationFactor: Parser[LogicalPlan] =
+    ident ~ (opt(AS) ~> opt(ident)) ^^ {
+      case ident ~ alias => UnresolvedRelation(alias, ident)
+    } |
+    "(" ~> query ~ ")" ~ opt(AS) ~ ident ^^ { case s ~ _ ~ _ ~ a => Subquery(a, s) }
+
+   protected lazy val joinedRelation: Parser[LogicalPlan] =
+     relationFactor ~ opt(joinType) ~ JOIN ~ relationFactor ~ opt(joinConditions) ^^ {
+      case r1 ~ jt ~ _ ~ r2 ~ cond =>
+        Join(r1, r2, joinType = jt.getOrElse(Inner), cond)
+     }
+
+   protected lazy val joinConditions: Parser[Expression] =
+     ON ~> expression
+
+   protected lazy val joinType: Parser[JoinType] =
+     INNER ^^^ Inner |
+     LEFT ~ opt(OUTER) ^^^ LeftOuter |
+     RIGHT ~ opt(OUTER) ^^^ RightOuter |
+     FULL ~ opt(OUTER) ^^^ FullOuter
+
+  protected lazy val filter: Parser[Expression] = WHERE ~ expression ^^ { case _ ~ e => e }
+
+  protected lazy val orderBy: Parser[Seq[SortOrder]] =
+    ORDER ~> BY ~> ordering
+
+  protected lazy val ordering: Parser[Seq[SortOrder]] =
+    rep1sep(singleOrder, ",") |
+    rep1sep(expression, ",") ~ opt(direction) ^^ {
+      case exps ~ None => exps.map(SortOrder(_, Ascending))
+      case exps ~ Some(d) => exps.map(SortOrder(_, d))
+    }
+
+  protected lazy val singleOrder: Parser[SortOrder] =
+    expression ~ direction ^^ { case e ~ o => SortOrder(e,o) }
+
+  protected lazy val direction: Parser[SortDirection] =
+    ASC ^^^ Ascending |
+    DESC ^^^ Descending
+
+  protected lazy val grouping: Parser[Seq[Expression]] =
+    GROUP ~> BY ~> rep1sep(expression, ",")
+
+  protected lazy val having: Parser[Expression] =
+    HAVING ~> expression
+
+  protected lazy val limit: Parser[Expression] =
+    LIMIT ~> expression
+
+  protected lazy val expression: Parser[Expression] = orExpression
+
+  protected lazy val orExpression: Parser[Expression] =
+    andExpression * (OR ^^^ { (e1: Expression, e2: Expression) => Or(e1,e2) })
+
+  protected lazy val andExpression: Parser[Expression] =
+    comparisionExpression * (AND ^^^ { (e1: Expression, e2: Expression) => And(e1,e2) })
+
+  protected lazy val comparisionExpression: Parser[Expression] =
+    termExpression ~ "=" ~ termExpression ^^ { case e1 ~ _ ~ e2 => Equals(e1, e2) } |
+    termExpression ~ "<" ~ termExpression ^^ { case e1 ~ _ ~ e2 => LessThan(e1, e2) } |
+    termExpression ~ "<=" ~ termExpression ^^ { case e1 ~ _ ~ e2 => LessThanOrEqual(e1, e2) } |
+    termExpression ~ ">" ~ termExpression ^^ { case e1 ~ _ ~ e2 => GreaterThan(e1, e2) } |
+    termExpression ~ ">=" ~ termExpression ^^ { case e1 ~ _ ~ e2 => GreaterThanOrEqual(e1, e2) } |
+    termExpression ~ "!=" ~ termExpression ^^ { case e1 ~ _ ~ e2 => Not(Equals(e1, e2)) } |
+    termExpression ~ "<>" ~ termExpression ^^ { case e1 ~ _ ~ e2 => Not(Equals(e1, e2)) } |
+    termExpression ~ IN ~ "(" ~ rep1sep(termExpression, ",") <~ ")" ^^ {
+      case e1 ~ _ ~ _ ~ e2 => In(e1, e2)
+    } |
+    termExpression ~ NOT ~ IN ~ "(" ~ rep1sep(termExpression, ",") <~ ")" ^^ {
+      case e1 ~ _ ~ _ ~ _ ~ e2 => Not(In(e1, e2))
+    } |
+    termExpression <~ IS ~ NULL ^^ { case e => IsNull(e) } |
+    termExpression <~ IS ~ NOT ~ NULL ^^ { case e => IsNotNull(e) } |
+    NOT ~> termExpression ^^ {e => Not(e)} |
+    termExpression
+
+  protected lazy val termExpression: Parser[Expression] =
+    productExpression * (
+      "+" ^^^ { (e1: Expression, e2: Expression) => Add(e1,e2) } |
+      "-" ^^^ { (e1: Expression, e2: Expression) => Subtract(e1,e2) } )
+
+  protected lazy val productExpression: Parser[Expression] =
+    baseExpression * (
+      "*" ^^^ { (e1: Expression, e2: Expression) => Multiply(e1,e2) } |
+      "/" ^^^ { (e1: Expression, e2: Expression) => Divide(e1,e2) } |
+      "%" ^^^ { (e1: Expression, e2: Expression) => Remainder(e1,e2) }
+    )
+
+  protected lazy val function: Parser[Expression] =
+    SUM ~> "(" ~> expression <~ ")" ^^ { case exp => Sum(exp) } |
+    SUM ~> "(" ~> DISTINCT ~> expression <~ ")" ^^ { case exp => SumDistinct(exp) } |
+    COUNT ~> "(" ~ "*" <~ ")" ^^ { case _ => Count(Literal(1)) } |
+    COUNT ~> "(" ~ expression <~ ")" ^^ { case dist ~ exp => Count(exp) } |
+    COUNT ~> "(" ~> DISTINCT ~> expression <~ ")" ^^ { case exp => CountDistinct(exp :: Nil) } |
+    FIRST ~> "(" ~> expression <~ ")" ^^ { case exp => First(exp) } |
+    AVG ~> "(" ~> expression <~ ")" ^^ { case exp => Average(exp) } |
+    IF ~> "(" ~> expression ~ "," ~ expression ~ "," ~ expression <~ ")" ^^ {
+      case c ~ "," ~ t ~ "," ~ f => If(c,t,f)
+    } |
+    ident ~ "(" ~ repsep(expression, ",") <~ ")" ^^ {
+      case udfName ~ _ ~ exprs => UnresolvedFunction(udfName, exprs)
+    }
+
+  protected lazy val cast: Parser[Expression] =
+    CAST ~> "(" ~> expression ~ AS ~ dataType <~ ")" ^^ { case exp ~ _ ~ t => Cast(exp, t) }
+
+  protected lazy val literal: Parser[Literal] =
+    numericLit ^^ {
+      case i if i.toLong > Int.MaxValue => Literal(i.toLong)
+      case i => Literal(i.toInt)
+    } |
+    NULL ^^^ Literal(null, NullType) |
+    floatLit ^^ {case f => Literal(f.toDouble) } |
+    stringLit ^^ {case s => Literal(s, StringType) }
+
+  protected lazy val floatLit: Parser[String] =
+    elem("decimal", _.isInstanceOf[lexical.FloatLit]) ^^ (_.chars)
+
+  protected lazy val baseExpression: Parser[Expression] =
+    TRUE ^^^ Literal(true, BooleanType) |
+    FALSE ^^^ Literal(false, BooleanType) |
+    cast |
+    "(" ~> expression <~ ")" |
+    function |
+    "-" ~> literal ^^ UnaryMinus |
+    ident ^^ UnresolvedAttribute |
+    "*" ^^^ Star(None) |
+    literal
+
+  protected lazy val dataType: Parser[DataType] =
+    STRING ^^^ StringType
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala
new file mode 100644
index 0000000000..9eb992ee58
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala
@@ -0,0 +1,185 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package analysis
+
+import expressions._
+import plans.logical._
+import rules._
+
+/**
+ * A trivial [[Analyzer]] with an [[EmptyCatalog]] and [[EmptyFunctionRegistry]]. Used for testing
+ * when all relations are already filled in and the analyser needs only to resolve attribute
+ * references.
+ */
+object SimpleAnalyzer extends Analyzer(EmptyCatalog, EmptyFunctionRegistry, true)
+
+/**
+ * Provides a logical query plan analyzer, which translates [[UnresolvedAttribute]]s and
+ * [[UnresolvedRelation]]s into fully typed objects using information in a schema [[Catalog]] and
+ * a [[FunctionRegistry]].
+ */
+class Analyzer(catalog: Catalog, registry: FunctionRegistry, caseSensitive: Boolean)
+  extends RuleExecutor[LogicalPlan] with HiveTypeCoercion {
+
+  // TODO: pass this in as a parameter.
+  val fixedPoint = FixedPoint(100)
+
+  val batches: Seq[Batch] = Seq(
+    Batch("MultiInstanceRelations", Once,
+      NewRelationInstances),
+    Batch("CaseInsensitiveAttributeReferences", Once,
+      (if (caseSensitive) Nil else LowercaseAttributeReferences :: Nil) : _*),
+    Batch("Resolution", fixedPoint,
+      ResolveReferences ::
+      ResolveRelations ::
+      NewRelationInstances ::
+      ImplicitGenerate ::
+      StarExpansion ::
+      ResolveFunctions ::
+      GlobalAggregates ::
+      typeCoercionRules :_*)
+  )
+
+  /**
+   * Replaces [[UnresolvedRelation]]s with concrete relations from the catalog.
+   */
+  object ResolveRelations extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+      case UnresolvedRelation(databaseName, name, alias) =>
+        catalog.lookupRelation(databaseName, name, alias)
+    }
+  }
+
+  /**
+   * Makes attribute naming case insensitive by turning all UnresolvedAttributes to lowercase.
+   */
+  object LowercaseAttributeReferences extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+      case UnresolvedRelation(databaseName, name, alias) =>
+        UnresolvedRelation(databaseName, name, alias.map(_.toLowerCase))
+      case Subquery(alias, child) => Subquery(alias.toLowerCase, child)
+      case q: LogicalPlan => q transformExpressions {
+        case s: Star => s.copy(table = s.table.map(_.toLowerCase))
+        case UnresolvedAttribute(name) => UnresolvedAttribute(name.toLowerCase)
+        case Alias(c, name) => Alias(c, name.toLowerCase)()
+      }
+    }
+  }
+
+  /**
+   * Replaces [[UnresolvedAttribute]]s with concrete
+   * [[expressions.AttributeReference AttributeReferences]] from a logical plan node's children.
+   */
+  object ResolveReferences extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transformUp {
+      case q: LogicalPlan if q.childrenResolved =>
+        logger.trace(s"Attempting to resolve ${q.simpleString}")
+        q transformExpressions {
+          case u @ UnresolvedAttribute(name) =>
+            // Leave unchanged if resolution fails.  Hopefully will be resolved next round.
+            val result = q.resolve(name).getOrElse(u)
+            logger.debug(s"Resolving $u to $result")
+            result
+        }
+    }
+  }
+
+  /**
+   * Replaces [[UnresolvedFunction]]s with concrete [[expressions.Expression Expressions]].
+   */
+  object ResolveFunctions extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+      case q: LogicalPlan =>
+        q transformExpressions {
+          case u @ UnresolvedFunction(name, children) if u.childrenResolved =>
+            registry.lookupFunction(name, children)
+        }
+    }
+  }
+
+  /**
+   * Turns projections that contain aggregate expressions into aggregations.
+   */
+  object GlobalAggregates extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+      case Project(projectList, child) if containsAggregates(projectList) =>
+        Aggregate(Nil, projectList, child)
+    }
+
+    def containsAggregates(exprs: Seq[Expression]): Boolean = {
+      exprs.foreach(_.foreach {
+        case agg: AggregateExpression => return true
+        case _ =>
+      })
+      false
+    }
+  }
+
+  /**
+   * When a SELECT clause has only a single expression and that expression is a
+   * [[catalyst.expressions.Generator Generator]] we convert the
+   * [[catalyst.plans.logical.Project Project]] to a [[catalyst.plans.logical.Generate Generate]].
+   */
+  object ImplicitGenerate extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+      case Project(Seq(Alias(g: Generator, _)), child) =>
+        Generate(g, join = false, outer = false, None, child)
+    }
+  }
+
+  /**
+   * Expands any references to [[Star]] (*) in project operators.
+   */
+  object StarExpansion extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+      // Wait until children are resolved
+      case p: LogicalPlan if !p.childrenResolved => p
+      // If the projection list contains Stars, expand it.
+      case p @ Project(projectList, child) if containsStar(projectList) =>
+        Project(
+          projectList.flatMap {
+            case s: Star => s.expand(child.output)
+            case o => o :: Nil
+          },
+          child)
+      case t: ScriptTransformation if containsStar(t.input) =>
+        t.copy(
+          input = t.input.flatMap {
+            case s: Star => s.expand(t.child.output)
+            case o => o :: Nil
+          }
+        )
+      // If the aggregate function argument contains Stars, expand it.
+      case a: Aggregate if containsStar(a.aggregateExpressions) =>
+        a.copy(
+          aggregateExpressions = a.aggregateExpressions.flatMap {
+            case s: Star => s.expand(a.child.output)
+            case o => o :: Nil
+          }
+        )
+    }
+
+    /**
+     * Returns true if `exprs` contains a [[Star]].
+     */
+    protected def containsStar(exprs: Seq[Expression]): Boolean =
+      exprs.collect { case _: Star => true }.nonEmpty
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Catalog.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Catalog.scala
new file mode 100644
index 0000000000..71e4dcdb15
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Catalog.scala
@@ -0,0 +1,107 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package analysis
+
+import plans.logical.{LogicalPlan, Subquery}
+import scala.collection.mutable
+
+/**
+ * An interface for looking up relations by name.  Used by an [[Analyzer]].
+ */
+trait Catalog {
+  def lookupRelation(
+    databaseName: Option[String],
+    tableName: String,
+    alias: Option[String] = None): LogicalPlan
+
+  def registerTable(databaseName: Option[String], tableName: String, plan: LogicalPlan): Unit
+}
+
+class SimpleCatalog extends Catalog {
+  val tables = new mutable.HashMap[String, LogicalPlan]()
+
+  def registerTable(databaseName: Option[String],tableName: String, plan: LogicalPlan): Unit = {
+    tables += ((tableName, plan))
+  }
+
+  def dropTable(tableName: String) = tables -= tableName
+
+  def lookupRelation(
+      databaseName: Option[String],
+      tableName: String,
+      alias: Option[String] = None): LogicalPlan = {
+    val table = tables.get(tableName).getOrElse(sys.error(s"Table Not Found: $tableName"))
+
+    // If an alias was specified by the lookup, wrap the plan in a subquery so that attributes are
+    // properly qualified with this alias.
+    alias.map(a => Subquery(a.toLowerCase, table)).getOrElse(table)
+  }
+}
+
+/**
+ * A trait that can be mixed in with other Catalogs allowing specific tables to be overridden with
+ * new logical plans.  This can be used to bind query result to virtual tables, or replace tables
+ * with in-memory cached versions.  Note that the set of overrides is stored in memory and thus
+ * lost when the JVM exits.
+ */
+trait OverrideCatalog extends Catalog {
+
+  // TODO: This doesn't work when the database changes...
+  val overrides = new mutable.HashMap[(Option[String],String), LogicalPlan]()
+
+  abstract override def lookupRelation(
+    databaseName: Option[String],
+    tableName: String,
+    alias: Option[String] = None): LogicalPlan = {
+
+    val overriddenTable = overrides.get((databaseName, tableName))
+
+    // If an alias was specified by the lookup, wrap the plan in a subquery so that attributes are
+    // properly qualified with this alias.
+    val withAlias =
+      overriddenTable.map(r => alias.map(a => Subquery(a.toLowerCase, r)).getOrElse(r))
+
+    withAlias.getOrElse(super.lookupRelation(databaseName, tableName, alias))
+  }
+
+  override def registerTable(
+      databaseName: Option[String],
+      tableName: String,
+      plan: LogicalPlan): Unit = {
+    overrides.put((databaseName, tableName), plan)
+  }
+}
+
+/**
+ * A trivial catalog that returns an error when a relation is requested.  Used for testing when all
+ * relations are already filled in and the analyser needs only to resolve attribute references.
+ */
+object EmptyCatalog extends Catalog {
+  def lookupRelation(
+    databaseName: Option[String],
+    tableName: String,
+    alias: Option[String] = None) = {
+    throw new UnsupportedOperationException
+  }
+
+  def registerTable(databaseName: Option[String], tableName: String, plan: LogicalPlan): Unit = {
+    throw new UnsupportedOperationException
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/FunctionRegistry.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/FunctionRegistry.scala
new file mode 100644
index 0000000000..a359eb5411
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/FunctionRegistry.scala
@@ -0,0 +1,37 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package analysis
+
+import expressions._
+
+/** A catalog for looking up user defined functions, used by an [[Analyzer]]. */
+trait FunctionRegistry {
+  def lookupFunction(name: String, children: Seq[Expression]): Expression
+}
+
+/**
+ * A trivial catalog that returns an error when a function is requested.  Used for testing when all
+ * functions are already filled in and the analyser needs only to resolve attribute references.
+ */
+object EmptyFunctionRegistry extends FunctionRegistry {
+  def lookupFunction(name: String, children: Seq[Expression]): Expression = {
+    throw new UnsupportedOperationException
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/HiveTypeCoercion.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/HiveTypeCoercion.scala
new file mode 100644
index 0000000000..a0105cd7cf
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/HiveTypeCoercion.scala
@@ -0,0 +1,275 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package analysis
+
+import expressions._
+import plans.logical._
+import rules._
+import types._
+
+/**
+ * A collection of [[catalyst.rules.Rule Rules]] that can be used to coerce differing types that
+ * participate in operations into compatible ones.  Most of these rules are based on Hive semantics,
+ * but they do not introduce any dependencies on the hive codebase.  For this reason they remain in
+ * Catalyst until we have a more standard set of coercions.
+ */
+trait HiveTypeCoercion {
+
+  val typeCoercionRules =
+    List(PropagateTypes, ConvertNaNs, WidenTypes, PromoteStrings, BooleanComparisons, BooleanCasts,
+      StringToIntegralCasts, FunctionArgumentConversion)
+
+  /**
+   * Applies any changes to [[catalyst.expressions.AttributeReference AttributeReference]] dataTypes
+   * that are made by other rules to instances higher in the query tree.
+   */
+  object PropagateTypes extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+      // No propagation required for leaf nodes.
+      case q: LogicalPlan if q.children.isEmpty => q
+
+      // Don't propagate types from unresolved children.
+      case q: LogicalPlan if !q.childrenResolved => q
+
+      case q: LogicalPlan => q transformExpressions {
+        case a: AttributeReference =>
+          q.inputSet.find(_.exprId == a.exprId) match {
+            // This can happen when a Attribute reference is born in a non-leaf node, for example
+            // due to a call to an external script like in the Transform operator.
+            // TODO: Perhaps those should actually be aliases?
+            case None => a
+            // Leave the same if the dataTypes match.
+            case Some(newType) if a.dataType == newType.dataType => a
+            case Some(newType) =>
+              logger.debug(s"Promoting $a to $newType in ${q.simpleString}}")
+              newType
+          }
+      }
+    }
+  }
+
+  /**
+   * Converts string "NaN"s that are in binary operators with a NaN-able types (Float / Double) to
+   * the appropriate numeric equivalent.
+   */
+  object ConvertNaNs extends Rule[LogicalPlan] {
+    val stringNaN = Literal("NaN", StringType)
+
+    def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+      case q: LogicalPlan => q transformExpressions {
+        // Skip nodes who's children have not been resolved yet.
+        case e if !e.childrenResolved => e
+
+        /* Double Conversions */
+        case b: BinaryExpression if b.left == stringNaN && b.right.dataType == DoubleType =>
+          b.makeCopy(Array(b.right, Literal(Double.NaN)))
+        case b: BinaryExpression if b.left.dataType == DoubleType && b.right == stringNaN =>
+          b.makeCopy(Array(Literal(Double.NaN), b.left))
+        case b: BinaryExpression if b.left == stringNaN && b.right == stringNaN =>
+          b.makeCopy(Array(Literal(Double.NaN), b.left))
+
+        /* Float Conversions */
+        case b: BinaryExpression if b.left == stringNaN && b.right.dataType == FloatType =>
+          b.makeCopy(Array(b.right, Literal(Float.NaN)))
+        case b: BinaryExpression if b.left.dataType == FloatType && b.right == stringNaN =>
+          b.makeCopy(Array(Literal(Float.NaN), b.left))
+        case b: BinaryExpression if b.left == stringNaN && b.right == stringNaN =>
+          b.makeCopy(Array(Literal(Float.NaN), b.left))
+      }
+    }
+  }
+
+  /**
+   * Widens numeric types and converts strings to numbers when appropriate.
+   *
+   * Loosely based on rules from "Hadoop: The Definitive Guide" 2nd edition, by Tom White
+   *
+   * The implicit conversion rules can be summarized as follows:
+   *   - Any integral numeric type can be implicitly converted to a wider type.
+   *   - All the integral numeric types, FLOAT, and (perhaps surprisingly) STRING can be implicitly
+   *     converted to DOUBLE.
+   *   - TINYINT, SMALLINT, and INT can all be converted to FLOAT.
+   *   - BOOLEAN types cannot be converted to any other type.
+   *
+   * Additionally, all types when UNION-ed with strings will be promoted to strings.
+   * Other string conversions are handled by PromoteStrings.
+   */
+  object WidenTypes extends Rule[LogicalPlan] {
+    // See https://cwiki.apache.org/confluence/display/Hive/LanguageManual+Types.
+    // The conversion for integral and floating point types have a linear widening hierarchy:
+    val numericPrecedence =
+      Seq(NullType, ByteType, ShortType, IntegerType, LongType, FloatType, DoubleType, DecimalType)
+    // Boolean is only wider than Void
+    val booleanPrecedence = Seq(NullType, BooleanType)
+    val allPromotions: Seq[Seq[DataType]] = numericPrecedence :: booleanPrecedence :: Nil
+
+    def findTightestCommonType(t1: DataType, t2: DataType): Option[DataType] = {
+      // Try and find a promotion rule that contains both types in question.
+      val applicableConversion = allPromotions.find(p => p.contains(t1) && p.contains(t2))
+
+      // If found return the widest common type, otherwise None
+      applicableConversion.map(_.filter(t => t == t1 || t == t2).last)
+    }
+
+    def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+      case u @ Union(left, right) if u.childrenResolved && !u.resolved =>
+        val castedInput = left.output.zip(right.output).map {
+          // When a string is found on one side, make the other side a string too.
+          case (l, r) if l.dataType == StringType && r.dataType != StringType =>
+            (l, Alias(Cast(r, StringType), r.name)())
+          case (l, r) if l.dataType != StringType && r.dataType == StringType =>
+            (Alias(Cast(l, StringType), l.name)(), r)
+
+          case (l, r) if l.dataType != r.dataType =>
+            logger.debug(s"Resolving mismatched union input ${l.dataType}, ${r.dataType}")
+            findTightestCommonType(l.dataType, r.dataType).map { widestType =>
+              val newLeft =
+                if (l.dataType == widestType) l else Alias(Cast(l, widestType), l.name)()
+              val newRight =
+                if (r.dataType == widestType) r else Alias(Cast(r, widestType), r.name)()
+
+              (newLeft, newRight)
+            }.getOrElse((l, r)) // If there is no applicable conversion, leave expression unchanged.
+          case other => other
+        }
+
+        val (castedLeft, castedRight) = castedInput.unzip
+
+        val newLeft =
+          if (castedLeft.map(_.dataType) != left.output.map(_.dataType)) {
+            logger.debug(s"Widening numeric types in union $castedLeft ${left.output}")
+            Project(castedLeft, left)
+          } else {
+            left
+          }
+
+        val newRight =
+          if (castedRight.map(_.dataType) != right.output.map(_.dataType)) {
+            logger.debug(s"Widening numeric types in union $castedRight ${right.output}")
+            Project(castedRight, right)
+          } else {
+            right
+          }
+
+        Union(newLeft, newRight)
+
+      // Also widen types for BinaryExpressions.
+      case q: LogicalPlan => q transformExpressions {
+        // Skip nodes who's children have not been resolved yet.
+        case e if !e.childrenResolved => e
+
+        case b: BinaryExpression if b.left.dataType != b.right.dataType =>
+          findTightestCommonType(b.left.dataType, b.right.dataType).map { widestType =>
+            val newLeft =
+              if (b.left.dataType == widestType) b.left else Cast(b.left, widestType)
+            val newRight =
+              if (b.right.dataType == widestType) b.right else Cast(b.right, widestType)
+            b.makeCopy(Array(newLeft, newRight))
+          }.getOrElse(b)  // If there is no applicable conversion, leave expression unchanged.
+      }
+    }
+  }
+
+  /**
+   * Promotes strings that appear in arithmetic expressions.
+   */
+  object PromoteStrings extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transformAllExpressions {
+      // Skip nodes who's children have not been resolved yet.
+      case e if !e.childrenResolved => e
+
+      case a: BinaryArithmetic if a.left.dataType == StringType =>
+        a.makeCopy(Array(Cast(a.left, DoubleType), a.right))
+      case a: BinaryArithmetic if a.right.dataType == StringType =>
+        a.makeCopy(Array(a.left, Cast(a.right, DoubleType)))
+
+      case p: BinaryPredicate if p.left.dataType == StringType && p.right.dataType != StringType =>
+        p.makeCopy(Array(Cast(p.left, DoubleType), p.right))
+      case p: BinaryPredicate if p.left.dataType != StringType && p.right.dataType == StringType =>
+        p.makeCopy(Array(p.left, Cast(p.right, DoubleType)))
+
+      case Sum(e) if e.dataType == StringType =>
+        Sum(Cast(e, DoubleType))
+      case Average(e) if e.dataType == StringType =>
+        Average(Cast(e, DoubleType))
+    }
+  }
+
+  /**
+   * Changes Boolean values to Bytes so that expressions like true < false can be Evaluated.
+   */
+  object BooleanComparisons extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transformAllExpressions {
+      // Skip nodes who's children have not been resolved yet.
+      case e if !e.childrenResolved => e
+      // No need to change Equals operators as that actually makes sense for boolean types.
+      case e: Equals => e
+      // Otherwise turn them to Byte types so that there exists and ordering.
+      case p: BinaryComparison
+          if p.left.dataType == BooleanType && p.right.dataType == BooleanType =>
+        p.makeCopy(Array(Cast(p.left, ByteType), Cast(p.right, ByteType)))
+    }
+  }
+
+  /**
+   * Casts to/from [[catalyst.types.BooleanType BooleanType]] are transformed into comparisons since
+   * the JVM does not consider Booleans to be numeric types.
+   */
+  object BooleanCasts extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transformAllExpressions {
+      // Skip nodes who's children have not been resolved yet.
+      case e if !e.childrenResolved => e
+
+      case Cast(e, BooleanType) => Not(Equals(e, Literal(0)))
+      case Cast(e, dataType) if e.dataType == BooleanType =>
+        Cast(If(e, Literal(1), Literal(0)), dataType)
+    }
+  }
+
+  /**
+   * When encountering a cast from a string representing a valid fractional number to an integral
+   * type the jvm will throw a `java.lang.NumberFormatException`.  Hive, in contrast, returns the
+   * truncated version of this number.
+   */
+  object StringToIntegralCasts extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transformAllExpressions {
+      // Skip nodes who's children have not been resolved yet.
+      case e if !e.childrenResolved => e
+
+      case Cast(e @ StringType(), t: IntegralType) =>
+        Cast(Cast(e, DecimalType), t)
+    }
+  }
+
+  /**
+   * This ensure that the types for various functions are as expected.
+   */
+  object FunctionArgumentConversion extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = plan transformAllExpressions {
+      // Skip nodes who's children have not been resolved yet.
+      case e if !e.childrenResolved => e
+
+      // Promote SUM to largest types to prevent overflows.
+      case s @ Sum(e @ DecimalType()) => s // Decimal is already the biggest.
+      case Sum(e @ IntegralType()) if e.dataType != LongType => Sum(Cast(e, LongType))
+      case Sum(e @ FractionalType()) if e.dataType != DoubleType => Sum(Cast(e, DoubleType))
+    }
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/MultiInstanceRelation.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/MultiInstanceRelation.scala
new file mode 100644
index 0000000000..fe18cc466f
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/MultiInstanceRelation.scala
@@ -0,0 +1,54 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql.catalyst
+package analysis
+
+import plans.logical.LogicalPlan
+import rules._
+
+/**
+ * A trait that should be mixed into query operators where an single instance might appear multiple
+ * times in a logical query plan.  It is invalid to have multiple copies of the same attribute
+ * produced by distinct operators in a query tree as this breaks the gurantee that expression
+ * ids, which are used to differentate attributes, are unique.
+ *
+ * Before analysis, all operators that include this trait will be asked to produce a new version
+ * of itself with globally unique expression ids.
+ */
+trait MultiInstanceRelation {
+  def newInstance: this.type
+}
+
+/**
+ * If any MultiInstanceRelation appears more than once in the query plan then the plan is updated so
+ * that each instance has unique expression ids for the attributes produced.
+ */
+object NewRelationInstances extends Rule[LogicalPlan] {
+  def apply(plan: LogicalPlan): LogicalPlan = {
+    val localRelations = plan collect { case l: MultiInstanceRelation => l}
+    val multiAppearance = localRelations
+      .groupBy(identity[MultiInstanceRelation])
+      .filter { case (_, ls) => ls.size > 1 }
+      .map(_._1)
+      .toSet
+
+    plan transform {
+      case l: MultiInstanceRelation if multiAppearance contains l => l.newInstance
+    }
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/package.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/package.scala
new file mode 100644
index 0000000000..375c99f48e
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/package.scala
@@ -0,0 +1,25 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package catalyst
+
+/**
+ * Provides a logical query plan [[Analyzer]] and supporting classes for performing analysis.
+ * Analysis consists of translating [[UnresolvedAttribute]]s and [[UnresolvedRelation]]s
+ * into fully typed objects using information in a schema [[Catalog]].
+ */
+package object analysis
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/unresolved.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/unresolved.scala
new file mode 100644
index 0000000000..2ed2af1352
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/unresolved.scala
@@ -0,0 +1,109 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package analysis
+
+import expressions._
+import plans.logical.BaseRelation
+import trees.TreeNode
+
+/**
+ * Thrown when an invalid attempt is made to access a property of a tree that has yet to be fully
+ * resolved.
+ */
+class UnresolvedException[TreeType <: TreeNode[_]](tree: TreeType, function: String) extends
+  errors.TreeNodeException(tree, s"Invalid call to $function on unresolved object", null)
+
+/**
+ * Holds the name of a relation that has yet to be looked up in a [[Catalog]].
+ */
+case class UnresolvedRelation(
+    databaseName: Option[String],
+    tableName: String,
+    alias: Option[String] = None) extends BaseRelation {
+  def output = Nil
+  override lazy val resolved = false
+}
+
+/**
+ * Holds the name of an attribute that has yet to be resolved.
+ */
+case class UnresolvedAttribute(name: String) extends Attribute with trees.LeafNode[Expression] {
+  def exprId = throw new UnresolvedException(this, "exprId")
+  def dataType = throw new UnresolvedException(this, "dataType")
+  def nullable = throw new UnresolvedException(this, "nullable")
+  def qualifiers = throw new UnresolvedException(this, "qualifiers")
+  override lazy val resolved = false
+
+  def newInstance = this
+  def withQualifiers(newQualifiers: Seq[String]) = this
+
+  override def toString: String = s"'$name"
+}
+
+case class UnresolvedFunction(name: String, children: Seq[Expression]) extends Expression {
+  def exprId = throw new UnresolvedException(this, "exprId")
+  def dataType = throw new UnresolvedException(this, "dataType")
+  override def foldable = throw new UnresolvedException(this, "foldable")
+  def nullable = throw new UnresolvedException(this, "nullable")
+  def qualifiers = throw new UnresolvedException(this, "qualifiers")
+  def references = children.flatMap(_.references).toSet
+  override lazy val resolved = false
+  override def toString = s"'$name(${children.mkString(",")})"
+}
+
+/**
+ * Represents all of the input attributes to a given relational operator, for example in
+ * "SELECT * FROM ...".
+ *
+ * @param table an optional table that should be the target of the expansion.  If omitted all
+ *              tables' columns are produced.
+ */
+case class Star(
+    table: Option[String],
+    mapFunction: Attribute => Expression = identity[Attribute])
+  extends Attribute with trees.LeafNode[Expression] {
+
+  def name = throw new UnresolvedException(this, "exprId")
+  def exprId = throw new UnresolvedException(this, "exprId")
+  def dataType = throw new UnresolvedException(this, "dataType")
+  def nullable = throw new UnresolvedException(this, "nullable")
+  def qualifiers = throw new UnresolvedException(this, "qualifiers")
+  override lazy val resolved = false
+
+  def newInstance = this
+  def withQualifiers(newQualifiers: Seq[String]) = this
+
+  def expand(input: Seq[Attribute]): Seq[NamedExpression] = {
+    val expandedAttributes: Seq[Attribute] = table match {
+      // If there is no table specified, use all input attributes.
+      case None => input
+      // If there is a table, pick out attributes that are part of this table.
+      case Some(table) => input.filter(_.qualifiers contains table)
+    }
+    val mappedAttributes = expandedAttributes.map(mapFunction).zip(input).map {
+      case (n: NamedExpression, _) => n
+      case (e, originalAttribute) =>
+        Alias(e, originalAttribute.name)(qualifiers = originalAttribute.qualifiers)
+    }
+    mappedAttributes
+  }
+
+  override def toString = table.map(_ + ".").getOrElse("") + "*"
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/dsl/package.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/dsl/package.scala
new file mode 100644
index 0000000000..cd8de9d52f
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/dsl/package.scala
@@ -0,0 +1,224 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+
+import scala.language.implicitConversions
+import scala.reflect.runtime.universe.TypeTag
+
+import analysis.UnresolvedAttribute
+import expressions._
+import plans._
+import plans.logical._
+import types._
+
+/**
+ * Provides experimental support for generating catalyst schemas for scala objects.
+ */
+object ScalaReflection {
+  import scala.reflect.runtime.universe._
+
+  /** Returns a Sequence of attributes for the given case class type. */
+  def attributesFor[T: TypeTag]: Seq[Attribute] = schemaFor[T] match {
+    case s: StructType =>
+      s.fields.map(f => AttributeReference(f.name, f.dataType, nullable = true)())
+  }
+
+  /** Returns a catalyst DataType for the given Scala Type using reflection. */
+  def schemaFor[T: TypeTag]: DataType = schemaFor(typeOf[T])
+
+  /** Returns a catalyst DataType for the given Scala Type using reflection. */
+  def schemaFor(tpe: `Type`): DataType = tpe match {
+    case t if t <:< typeOf[Product] =>
+      val params = t.member("<init>": TermName).asMethod.paramss
+      StructType(
+        params.head.map(p => StructField(p.name.toString, schemaFor(p.typeSignature), true)))
+    case t if t <:< typeOf[Seq[_]] =>
+      val TypeRef(_, _, Seq(elementType)) = t
+      ArrayType(schemaFor(elementType))
+    case t if t <:< typeOf[String] => StringType
+    case t if t <:< definitions.IntTpe => IntegerType
+    case t if t <:< definitions.LongTpe => LongType
+    case t if t <:< definitions.DoubleTpe => DoubleType
+    case t if t <:< definitions.ShortTpe => ShortType
+    case t if t <:< definitions.ByteTpe => ByteType
+  }
+
+  implicit class CaseClassRelation[A <: Product : TypeTag](data: Seq[A]) {
+
+    /**
+     * Implicitly added to Sequences of case class objects.  Returns a catalyst logical relation
+     * for the the data in the sequence.
+     */
+    def asRelation: LocalRelation = {
+      val output = attributesFor[A]
+      LocalRelation(output, data)
+    }
+  }
+}
+
+/**
+ * A collection of implicit conversions that create a DSL for constructing catalyst data structures.
+ *
+ * {{{
+ *  scala> import catalyst.dsl._
+ *
+ *  // Standard operators are added to expressions.
+ *  scala> Literal(1) + Literal(1)
+ *  res1: catalyst.expressions.Add = (1 + 1)
+ *
+ *  // There is a conversion from 'symbols to unresolved attributes.
+ *  scala> 'a.attr
+ *  res2: catalyst.analysis.UnresolvedAttribute = 'a
+ *
+ *  // These unresolved attributes can be used to create more complicated expressions.
+ *  scala> 'a === 'b
+ *  res3: catalyst.expressions.Equals = ('a = 'b)
+ *
+ *  // SQL verbs can be used to construct logical query plans.
+ *  scala> TestRelation('key.int, 'value.string).where('key === 1).select('value).analyze
+ *  res4: catalyst.plans.logical.LogicalPlan =
+ *  Project {value#1}
+ *   Filter (key#0 = 1)
+ *    TestRelation {key#0,value#1}
+ * }}}
+ */
+package object dsl {
+  trait ImplicitOperators {
+    def expr: Expression
+
+    def + (other: Expression) = Add(expr, other)
+    def - (other: Expression) = Subtract(expr, other)
+    def * (other: Expression) = Multiply(expr, other)
+    def / (other: Expression) = Divide(expr, other)
+
+    def && (other: Expression) = And(expr, other)
+    def || (other: Expression) = Or(expr, other)
+
+    def < (other: Expression) = LessThan(expr, other)
+    def <= (other: Expression) = LessThanOrEqual(expr, other)
+    def > (other: Expression) = GreaterThan(expr, other)
+    def >= (other: Expression) = GreaterThanOrEqual(expr, other)
+    def === (other: Expression) = Equals(expr, other)
+    def != (other: Expression) = Not(Equals(expr, other))
+
+    def asc = SortOrder(expr, Ascending)
+    def desc = SortOrder(expr, Descending)
+
+    def as(s: Symbol) = Alias(expr, s.name)()
+  }
+
+  trait ExpressionConversions {
+    implicit class DslExpression(e: Expression) extends ImplicitOperators {
+      def expr = e
+    }
+
+    implicit def intToLiteral(i: Int) = Literal(i)
+    implicit def longToLiteral(l: Long) = Literal(l)
+    implicit def floatToLiteral(f: Float) = Literal(f)
+    implicit def doubleToLiteral(d: Double) = Literal(d)
+    implicit def stringToLiteral(s: String) = Literal(s)
+
+    implicit def symbolToUnresolvedAttribute(s: Symbol) = analysis.UnresolvedAttribute(s.name)
+
+    implicit class DslSymbol(sym: Symbol) extends ImplicitAttribute { def s = sym.name }
+    implicit class DslString(val s: String) extends ImplicitAttribute
+
+    abstract class ImplicitAttribute extends ImplicitOperators {
+      def s: String
+      def expr = attr
+      def attr = analysis.UnresolvedAttribute(s)
+
+      /** Creates a new typed attributes of type int */
+      def int = AttributeReference(s, IntegerType, nullable = false)()
+
+      /** Creates a new typed attributes of type string */
+      def string = AttributeReference(s, StringType, nullable = false)()
+    }
+
+    implicit class DslAttribute(a: AttributeReference) {
+      def notNull = a.withNullability(false)
+      def nullable = a.withNullability(true)
+
+      // Protobuf terminology
+      def required = a.withNullability(false)
+    }
+  }
+
+
+  object expressions extends ExpressionConversions  // scalastyle:ignore
+
+  abstract class LogicalPlanFunctions {
+    def logicalPlan: LogicalPlan
+
+    def select(exprs: NamedExpression*) = Project(exprs, logicalPlan)
+
+    def where(condition: Expression) = Filter(condition, logicalPlan)
+
+    def join(
+        otherPlan: LogicalPlan,
+        joinType: JoinType = Inner,
+        condition: Option[Expression] = None) =
+      Join(logicalPlan, otherPlan, joinType, condition)
+
+    def orderBy(sortExprs: SortOrder*) = Sort(sortExprs, logicalPlan)
+
+    def groupBy(groupingExprs: Expression*)(aggregateExprs: Expression*) = {
+      val aliasedExprs = aggregateExprs.map {
+        case ne: NamedExpression => ne
+        case e => Alias(e, e.toString)()
+      }
+      Aggregate(groupingExprs, aliasedExprs, logicalPlan)
+    }
+
+    def subquery(alias: Symbol) = Subquery(alias.name, logicalPlan)
+
+    def unionAll(otherPlan: LogicalPlan) = Union(logicalPlan, otherPlan)
+
+    def sfilter[T1](arg1: Symbol)(udf: (T1) => Boolean) =
+      Filter(ScalaUdf(udf, BooleanType, Seq(UnresolvedAttribute(arg1.name))), logicalPlan)
+
+    def sfilter(dynamicUdf: (DynamicRow) => Boolean) =
+      Filter(ScalaUdf(dynamicUdf, BooleanType, Seq(WrapDynamic(logicalPlan.output))), logicalPlan)
+
+    def sample(
+        fraction: Double,
+        withReplacement: Boolean = true,
+        seed: Int = (math.random * 1000).toInt) =
+      Sample(fraction, withReplacement, seed, logicalPlan)
+
+    def generate(
+        generator: Generator,
+        join: Boolean = false,
+        outer: Boolean = false,
+        alias: Option[String] = None) =
+      Generate(generator, join, outer, None, logicalPlan)
+
+    def insertInto(tableName: String, overwrite: Boolean = false) =
+      InsertIntoTable(
+        analysis.UnresolvedRelation(None, tableName), Map.empty, logicalPlan, overwrite)
+
+    def analyze = analysis.SimpleAnalyzer(logicalPlan)
+  }
+
+  object plans {  // scalastyle:ignore
+    implicit class DslLogicalPlan(val logicalPlan: LogicalPlan) extends LogicalPlanFunctions {
+      def writeToFile(path: String) = WriteToFile(path, logicalPlan)
+    }
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/errors/package.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/errors/package.scala
new file mode 100644
index 0000000000..c253587f67
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/errors/package.scala
@@ -0,0 +1,57 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+
+import trees._
+
+/**
+ * Functions for attaching and retrieving trees that are associated with errors.
+ */
+package object errors {
+
+  class TreeNodeException[TreeType <: TreeNode[_]]
+    (tree: TreeType, msg: String, cause: Throwable) extends Exception(msg, cause) {
+
+    // Yes, this is the same as a default parameter, but... those don't seem to work with SBT
+    // external project dependencies for some reason.
+    def this(tree: TreeType, msg: String) = this(tree, msg, null)
+
+    override def getMessage: String = {
+      val treeString = tree.toString
+      s"${super.getMessage}, tree:${if (treeString contains "\n") "\n" else " "}$tree"
+    }
+  }
+
+  /**
+   *  Wraps any exceptions that are thrown while executing `f` in a
+   *  [[catalyst.errors.TreeNodeException TreeNodeException]], attaching the provided `tree`.
+   */
+  def attachTree[TreeType <: TreeNode[_], A](tree: TreeType, msg: String = "")(f: => A): A = {
+    try f catch {
+      case e: Exception => throw new TreeNodeException(tree, msg, e)
+    }
+  }
+
+  /**
+   * Executes `f` which is expected to throw a
+   * [[catalyst.errors.TreeNodeException TreeNodeException]]. The first tree encountered in
+   * the stack of exceptions of type `TreeType` is returned.
+   */
+  def getTree[TreeType <: TreeNode[_]](f: => Unit): TreeType = ??? // TODO: Implement
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/BoundAttribute.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/BoundAttribute.scala
new file mode 100644
index 0000000000..3b6bac16ff
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/BoundAttribute.scala
@@ -0,0 +1,83 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import rules._
+import errors._
+
+import catalyst.plans.QueryPlan
+
+/**
+ * A bound reference points to a specific slot in the input tuple, allowing the actual value
+ * to be retrieved more efficiently.  However, since operations like column pruning can change
+ * the layout of intermediate tuples, BindReferences should be run after all such transformations.
+ */
+case class BoundReference(ordinal: Int, baseReference: Attribute)
+  extends Attribute with trees.LeafNode[Expression] {
+
+  type EvaluatedType = Any
+
+  def nullable = baseReference.nullable
+  def dataType = baseReference.dataType
+  def exprId = baseReference.exprId
+  def qualifiers = baseReference.qualifiers
+  def name = baseReference.name
+
+  def newInstance = BoundReference(ordinal, baseReference.newInstance)
+  def withQualifiers(newQualifiers: Seq[String]) =
+    BoundReference(ordinal, baseReference.withQualifiers(newQualifiers))
+
+  override def toString = s"$baseReference:$ordinal"
+
+  override def apply(input: Row): Any = input(ordinal)
+}
+
+class BindReferences[TreeNode <: QueryPlan[TreeNode]] extends Rule[TreeNode] {
+  import BindReferences._
+
+  def apply(plan: TreeNode): TreeNode = {
+    plan.transform {
+      case leafNode if leafNode.children.isEmpty => leafNode
+      case unaryNode if unaryNode.children.size == 1 => unaryNode.transformExpressions { case e =>
+        bindReference(e, unaryNode.children.head.output)
+      }
+    }
+  }
+}
+
+object BindReferences extends Logging {
+  def bindReference(expression: Expression, input: Seq[Attribute]): Expression = {
+    expression.transform { case a: AttributeReference =>
+      attachTree(a, "Binding attribute") {
+        val ordinal = input.indexWhere(_.exprId == a.exprId)
+        if (ordinal == -1) {
+          // TODO: This fallback is required because some operators (such as ScriptTransform)
+          // produce new attributes that can't be bound.  Likely the right thing to do is remove
+          // this rule and require all operators to explicitly bind to the input schema that
+          // they specify.
+          logger.debug(s"Couldn't find $a in ${input.mkString("[", ",", "]")}")
+          a
+        } else {
+          BoundReference(ordinal, a)
+        }
+      }
+    }
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Cast.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Cast.scala
new file mode 100644
index 0000000000..608656d3a9
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Cast.scala
@@ -0,0 +1,79 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import types._
+
+/** Cast the child expression to the target data type. */
+case class Cast(child: Expression, dataType: DataType) extends UnaryExpression {
+  override def foldable = child.foldable
+  def nullable = child.nullable
+  override def toString = s"CAST($child, $dataType)"
+
+  type EvaluatedType = Any
+
+  lazy val castingFunction: Any => Any = (child.dataType, dataType) match {
+    case (BinaryType, StringType) => a: Any => new String(a.asInstanceOf[Array[Byte]])
+    case (StringType, BinaryType) => a: Any => a.asInstanceOf[String].getBytes
+    case (_, StringType) => a: Any => a.toString
+    case (StringType, IntegerType) => a: Any => castOrNull(a, _.toInt)
+    case (StringType, DoubleType) => a: Any => castOrNull(a, _.toDouble)
+    case (StringType, FloatType) => a: Any => castOrNull(a, _.toFloat)
+    case (StringType, LongType) => a: Any => castOrNull(a, _.toLong)
+    case (StringType, ShortType) => a: Any => castOrNull(a, _.toShort)
+    case (StringType, ByteType) => a: Any => castOrNull(a, _.toByte)
+    case (StringType, DecimalType) => a: Any => castOrNull(a, BigDecimal(_))
+    case (BooleanType, ByteType) => a: Any => a match {
+      case null => null
+      case true => 1.toByte
+      case false => 0.toByte
+    }
+    case (dt, IntegerType) =>
+      a: Any => dt.asInstanceOf[NumericType].numeric.asInstanceOf[Numeric[Any]].toInt(a)
+    case (dt, DoubleType) =>
+      a: Any => dt.asInstanceOf[NumericType].numeric.asInstanceOf[Numeric[Any]].toDouble(a)
+    case (dt, FloatType) =>
+      a: Any => dt.asInstanceOf[NumericType].numeric.asInstanceOf[Numeric[Any]].toFloat(a)
+    case (dt, LongType) =>
+      a: Any => dt.asInstanceOf[NumericType].numeric.asInstanceOf[Numeric[Any]].toLong(a)
+    case (dt, ShortType) =>
+      a: Any => dt.asInstanceOf[NumericType].numeric.asInstanceOf[Numeric[Any]].toInt(a).toShort
+    case (dt, ByteType) =>
+      a: Any => dt.asInstanceOf[NumericType].numeric.asInstanceOf[Numeric[Any]].toInt(a).toByte
+    case (dt, DecimalType) =>
+      a: Any =>
+        BigDecimal(dt.asInstanceOf[NumericType].numeric.asInstanceOf[Numeric[Any]].toDouble(a))
+  }
+
+  @inline
+  protected def castOrNull[A](a: Any, f: String => A) =
+    try f(a.asInstanceOf[String]) catch {
+      case _: java.lang.NumberFormatException => null
+    }
+
+  override def apply(input: Row): Any = {
+    val evaluated = child.apply(input)
+    if (evaluated == null) {
+      null
+    } else {
+      castingFunction(evaluated)
+    }
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Expression.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Expression.scala
new file mode 100644
index 0000000000..78aaaeebbd
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Expression.scala
@@ -0,0 +1,196 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import errors._
+import trees._
+import types._
+
+abstract class Expression extends TreeNode[Expression] {
+  self: Product =>
+
+  /** The narrowest possible type that is produced when this expression is evaluated. */
+  type EvaluatedType <: Any
+
+  def dataType: DataType
+
+  /**
+   * Returns true when an expression is a candidate for static evaluation before the query is
+   * executed.
+   *
+   * The following conditions are used to determine suitability for constant folding:
+   *  - A [[expressions.Coalesce Coalesce]] is foldable if all of its children are foldable
+   *  - A [[expressions.BinaryExpression BinaryExpression]] is foldable if its both left and right
+   *    child are foldable
+   *  - A [[expressions.Not Not]], [[expressions.IsNull IsNull]], or
+   *    [[expressions.IsNotNull IsNotNull]] is foldable if its child is foldable.
+   *  - A [[expressions.Literal]] is foldable.
+   *  - A [[expressions.Cast Cast]] or [[expressions.UnaryMinus UnaryMinus]] is foldable if its
+   *    child is foldable.
+   */
+  // TODO: Supporting more foldable expressions. For example, deterministic Hive UDFs.
+  def foldable: Boolean = false
+  def nullable: Boolean
+  def references: Set[Attribute]
+
+  /** Returns the result of evaluating this expression on a given input Row */
+  def apply(input: Row = null): EvaluatedType =
+    throw new TreeNodeException(this, s"No function to evaluate expression. type: ${this.nodeName}")
+
+  /**
+   * Returns `true` if this expression and all its children have been resolved to a specific schema
+   * and `false` if it is still contains any unresolved placeholders. Implementations of expressions
+   * should override this if the resolution of this type of expression involves more than just
+   * the resolution of its children.
+   */
+  lazy val resolved: Boolean = childrenResolved
+
+  /**
+   * Returns true if  all the children of this expression have been resolved to a specific schema
+   * and false if any still contains any unresolved placeholders.
+   */
+  def childrenResolved = !children.exists(!_.resolved)
+
+  /**
+   * A set of helper functions that return the correct descendant of [[scala.math.Numeric]] type
+   * and do any casting necessary of child evaluation.
+   */
+  @inline
+  def n1(e: Expression, i: Row, f: ((Numeric[Any], Any) => Any)): Any  = {
+    val evalE = e.apply(i)
+    if (evalE == null) {
+      null
+    } else {
+      e.dataType match {
+        case n: NumericType =>
+          val castedFunction = f.asInstanceOf[(Numeric[n.JvmType], n.JvmType) => n.JvmType]
+          castedFunction(n.numeric, evalE.asInstanceOf[n.JvmType])
+        case other => sys.error(s"Type $other does not support numeric operations")
+      }
+    }
+  }
+
+  @inline
+  protected final def n2(
+      i: Row,
+      e1: Expression,
+      e2: Expression,
+      f: ((Numeric[Any], Any, Any) => Any)): Any  = {
+
+    if (e1.dataType != e2.dataType) {
+      throw new TreeNodeException(this,  s"Types do not match ${e1.dataType} != ${e2.dataType}")
+    }
+
+    val evalE1 = e1.apply(i)
+    if(evalE1 == null) {
+      null
+    } else {
+      val evalE2 = e2.apply(i)
+      if (evalE2 == null) {
+        null
+      } else {
+        e1.dataType match {
+          case n: NumericType =>
+            f.asInstanceOf[(Numeric[n.JvmType], n.JvmType, n.JvmType) => Int](
+              n.numeric, evalE1.asInstanceOf[n.JvmType], evalE2.asInstanceOf[n.JvmType])
+          case other => sys.error(s"Type $other does not support numeric operations")
+        }
+      }
+    }
+  }
+
+  @inline
+  protected final def f2(
+      i: Row,
+      e1: Expression,
+      e2: Expression,
+      f: ((Fractional[Any], Any, Any) => Any)): Any  = {
+    if (e1.dataType != e2.dataType) {
+      throw new TreeNodeException(this,  s"Types do not match ${e1.dataType} != ${e2.dataType}")
+    }
+
+    val evalE1 = e1.apply(i: Row)
+    if(evalE1 == null) {
+      null
+    } else {
+      val evalE2 = e2.apply(i: Row)
+      if (evalE2 == null) {
+        null
+      } else {
+        e1.dataType match {
+          case ft: FractionalType =>
+            f.asInstanceOf[(Fractional[ft.JvmType], ft.JvmType, ft.JvmType) => ft.JvmType](
+              ft.fractional, evalE1.asInstanceOf[ft.JvmType], evalE2.asInstanceOf[ft.JvmType])
+          case other => sys.error(s"Type $other does not support fractional operations")
+        }
+      }
+    }
+  }
+
+  @inline
+  protected final def i2(
+      i: Row,
+      e1: Expression,
+      e2: Expression,
+      f: ((Integral[Any], Any, Any) => Any)): Any  = {
+    if (e1.dataType != e2.dataType) {
+      throw new TreeNodeException(this,  s"Types do not match ${e1.dataType} != ${e2.dataType}")
+    }
+
+    val evalE1 = e1.apply(i)
+    if(evalE1 == null) {
+      null
+    } else {
+      val evalE2 = e2.apply(i)
+      if (evalE2 == null) {
+        null
+      } else {
+        e1.dataType match {
+          case i: IntegralType =>
+            f.asInstanceOf[(Integral[i.JvmType], i.JvmType, i.JvmType) => i.JvmType](
+              i.integral, evalE1.asInstanceOf[i.JvmType], evalE2.asInstanceOf[i.JvmType])
+          case other => sys.error(s"Type $other does not support numeric operations")
+        }
+      }
+    }
+  }
+}
+
+abstract class BinaryExpression extends Expression with trees.BinaryNode[Expression] {
+  self: Product =>
+
+  def symbol: String
+
+  override def foldable = left.foldable && right.foldable
+
+  def references = left.references ++ right.references
+
+  override def toString = s"($left $symbol $right)"
+}
+
+abstract class LeafExpression extends Expression with trees.LeafNode[Expression] {
+  self: Product =>
+}
+
+abstract class UnaryExpression extends Expression with trees.UnaryNode[Expression] {
+  self: Product =>
+
+  def references = child.references
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Projection.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Projection.scala
new file mode 100644
index 0000000000..8c407d2fdd
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Projection.scala
@@ -0,0 +1,127 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql.catalyst
+package expressions
+
+/**
+ * Converts a [[Row]] to another Row given a sequence of expression that define each column of the
+ * new row. If the schema of the input row is specified, then the given expression will be bound to
+ * that schema.
+ */
+class Projection(expressions: Seq[Expression]) extends (Row => Row) {
+  def this(expressions: Seq[Expression], inputSchema: Seq[Attribute]) =
+    this(expressions.map(BindReferences.bindReference(_, inputSchema)))
+
+  protected val exprArray = expressions.toArray
+  def apply(input: Row): Row = {
+    val outputArray = new Array[Any](exprArray.size)
+    var i = 0
+    while (i < exprArray.size) {
+      outputArray(i) = exprArray(i).apply(input)
+      i += 1
+    }
+    new GenericRow(outputArray)
+  }
+}
+
+/**
+ * Converts a [[Row]] to another Row given a sequence of expression that define each column of th
+ * new row. If the schema of the input row is specified, then the given expression will be bound to
+ * that schema.
+ *
+ * In contrast to a normal projection, a MutableProjection reuses the same underlying row object
+ * each time an input row is added.  This significatly reduces the cost of calcuating the
+ * projection, but means that it is not safe
+ */
+case class MutableProjection(expressions: Seq[Expression]) extends (Row => Row) {
+  def this(expressions: Seq[Expression], inputSchema: Seq[Attribute]) =
+    this(expressions.map(BindReferences.bindReference(_, inputSchema)))
+
+  private[this] val exprArray = expressions.toArray
+  private[this] val mutableRow = new GenericMutableRow(exprArray.size)
+  def currentValue: Row = mutableRow
+
+  def apply(input: Row): Row = {
+    var i = 0
+    while (i < exprArray.size) {
+      mutableRow(i) = exprArray(i).apply(input)
+      i += 1
+    }
+    mutableRow
+  }
+}
+
+/**
+ * A mutable wrapper that makes two rows appear appear as a single concatenated row.  Designed to
+ * be instantiated once per thread and reused.
+ */
+class JoinedRow extends Row {
+  private[this] var row1: Row = _
+  private[this] var row2: Row = _
+
+  /** Updates this JoinedRow to used point at two new base rows.  Returns itself. */
+  def apply(r1: Row, r2: Row): Row = {
+    row1 = r1
+    row2 = r2
+    this
+  }
+
+  def iterator = row1.iterator ++ row2.iterator
+
+  def length = row1.length + row2.length
+
+  def apply(i: Int) =
+    if (i < row1.size) row1(i) else row2(i - row1.size)
+
+  def isNullAt(i: Int) = apply(i) == null
+
+  def getInt(i: Int): Int =
+    if (i < row1.size) row1.getInt(i) else row2.getInt(i - row1.size)
+
+  def getLong(i: Int): Long =
+    if (i < row1.size) row1.getLong(i) else row2.getLong(i - row1.size)
+
+  def getDouble(i: Int): Double =
+    if (i < row1.size) row1.getDouble(i) else row2.getDouble(i - row1.size)
+
+  def getBoolean(i: Int): Boolean =
+    if (i < row1.size) row1.getBoolean(i) else row2.getBoolean(i - row1.size)
+
+  def getShort(i: Int): Short =
+    if (i < row1.size) row1.getShort(i) else row2.getShort(i - row1.size)
+
+  def getByte(i: Int): Byte =
+    if (i < row1.size) row1.getByte(i) else row2.getByte(i - row1.size)
+
+  def getFloat(i: Int): Float =
+    if (i < row1.size) row1.getFloat(i) else row2.getFloat(i - row1.size)
+
+  def getString(i: Int): String =
+    if (i < row1.size) row1.getString(i) else row2.getString(i - row1.size)
+
+  def copy() = {
+    val totalSize = row1.size + row2.size
+    val copiedValues = new Array[Any](totalSize)
+    var i = 0
+    while(i < totalSize) {
+      copiedValues(i) = apply(i)
+      i += 1
+    }
+    new GenericRow(copiedValues)
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Rand.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Rand.scala
new file mode 100644
index 0000000000..a5d0ecf964
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Rand.scala
@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import types.DoubleType
+
+case object Rand extends LeafExpression {
+  def dataType = DoubleType
+  def nullable = false
+  def references = Set.empty
+  override def toString = "RAND()"
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Row.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Row.scala
new file mode 100644
index 0000000000..3529675468
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Row.scala
@@ -0,0 +1,214 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import types._
+
+/**
+ * Represents one row of output from a relational operator.  Allows both generic access by ordinal,
+ * which will incur boxing overhead for primitives, as well as native primitive access.
+ *
+ * It is invalid to use the native primitive interface to retrieve a value that is null, instead a
+ * user must check [[isNullAt]] before attempting to retrieve a value that might be null.
+ */
+trait Row extends Seq[Any] with Serializable {
+  def apply(i: Int): Any
+
+  def isNullAt(i: Int): Boolean
+
+  def getInt(i: Int): Int
+  def getLong(i: Int): Long
+  def getDouble(i: Int): Double
+  def getFloat(i: Int): Float
+  def getBoolean(i: Int): Boolean
+  def getShort(i: Int): Short
+  def getByte(i: Int): Byte
+  def getString(i: Int): String
+
+  override def toString() =
+    s"[${this.mkString(",")}]"
+
+  def copy(): Row
+}
+
+/**
+ * An extended interface to [[Row]] that allows the values for each column to be updated.  Setting
+ * a value through a primitive function implicitly marks that column as not null.
+ */
+trait MutableRow extends Row {
+  def setNullAt(i: Int): Unit
+
+  def update(ordinal: Int, value: Any)
+
+  def setInt(ordinal: Int, value: Int)
+  def setLong(ordinal: Int, value: Long)
+  def setDouble(ordinal: Int, value: Double)
+  def setBoolean(ordinal: Int, value: Boolean)
+  def setShort(ordinal: Int, value: Short)
+  def setByte(ordinal: Int, value: Byte)
+  def setFloat(ordinal: Int, value: Float)
+  def setString(ordinal: Int, value: String)
+
+  /**
+   * EXPERIMENTAL
+   *
+   * Returns a mutable string builder for the specified column.  A given row should return the
+   * result of any mutations made to the returned buffer next time getString is called for the same
+   * column.
+   */
+  def getStringBuilder(ordinal: Int): StringBuilder
+}
+
+/**
+ * A row with no data.  Calling any methods will result in an error.  Can be used as a placeholder.
+ */
+object EmptyRow extends Row {
+  def apply(i: Int): Any = throw new UnsupportedOperationException
+
+  def iterator = Iterator.empty
+  def length = 0
+  def isNullAt(i: Int): Boolean = throw new UnsupportedOperationException
+
+  def getInt(i: Int): Int = throw new UnsupportedOperationException
+  def getLong(i: Int): Long = throw new UnsupportedOperationException
+  def getDouble(i: Int): Double = throw new UnsupportedOperationException
+  def getFloat(i: Int): Float = throw new UnsupportedOperationException
+  def getBoolean(i: Int): Boolean = throw new UnsupportedOperationException
+  def getShort(i: Int): Short = throw new UnsupportedOperationException
+  def getByte(i: Int): Byte = throw new UnsupportedOperationException
+  def getString(i: Int): String = throw new UnsupportedOperationException
+
+  def copy() = this
+}
+
+/**
+ * A row implementation that uses an array of objects as the underlying storage.  Note that, while
+ * the array is not copied, and thus could technically be mutated after creation, this is not
+ * allowed.
+ */
+class GenericRow(protected[catalyst] val values: Array[Any]) extends Row {
+  /** No-arg constructor for serialization. */
+  def this() = this(null)
+
+  def this(size: Int) = this(new Array[Any](size))
+
+  def iterator = values.iterator
+
+  def length = values.length
+
+  def apply(i: Int) = values(i)
+
+  def isNullAt(i: Int) = values(i) == null
+
+  def getInt(i: Int): Int = {
+    if (values(i) == null) sys.error("Failed to check null bit for primitive int value.")
+    values(i).asInstanceOf[Int]
+  }
+
+  def getLong(i: Int): Long = {
+    if (values(i) == null) sys.error("Failed to check null bit for primitive long value.")
+    values(i).asInstanceOf[Long]
+  }
+
+  def getDouble(i: Int): Double = {
+    if (values(i) == null) sys.error("Failed to check null bit for primitive double value.")
+    values(i).asInstanceOf[Double]
+  }
+
+  def getFloat(i: Int): Float = {
+    if (values(i) == null) sys.error("Failed to check null bit for primitive float value.")
+    values(i).asInstanceOf[Float]
+  }
+
+  def getBoolean(i: Int): Boolean = {
+    if (values(i) == null) sys.error("Failed to check null bit for primitive boolean value.")
+    values(i).asInstanceOf[Boolean]
+  }
+
+  def getShort(i: Int): Short = {
+    if (values(i) == null) sys.error("Failed to check null bit for primitive short value.")
+    values(i).asInstanceOf[Short]
+  }
+
+  def getByte(i: Int): Byte = {
+    if (values(i) == null) sys.error("Failed to check null bit for primitive byte value.")
+    values(i).asInstanceOf[Byte]
+  }
+
+  def getString(i: Int): String = {
+    if (values(i) == null) sys.error("Failed to check null bit for primitive String value.")
+    values(i).asInstanceOf[String]
+  }
+
+  def copy() = this
+}
+
+class GenericMutableRow(size: Int) extends GenericRow(size) with MutableRow {
+  /** No-arg constructor for serialization. */
+  def this() = this(0)
+
+  def getStringBuilder(ordinal: Int): StringBuilder = ???
+
+  override def setBoolean(ordinal: Int,value: Boolean): Unit = { values(ordinal) = value }
+  override def setByte(ordinal: Int,value: Byte): Unit = { values(ordinal) = value }
+  override def setDouble(ordinal: Int,value: Double): Unit = { values(ordinal) = value }
+  override def setFloat(ordinal: Int,value: Float): Unit = { values(ordinal) = value }
+  override def setInt(ordinal: Int,value: Int): Unit = { values(ordinal) = value }
+  override def setLong(ordinal: Int,value: Long): Unit = { values(ordinal) = value }
+  override def setString(ordinal: Int,value: String): Unit = { values(ordinal) = value }
+
+  override def setNullAt(i: Int): Unit = { values(i) = null }
+
+  override def setShort(ordinal: Int,value: Short): Unit = { values(ordinal) = value }
+
+  override def update(ordinal: Int,value: Any): Unit = { values(ordinal) = value }
+
+  override def copy() = new GenericRow(values.clone())
+}
+
+
+class RowOrdering(ordering: Seq[SortOrder]) extends Ordering[Row] {
+  def compare(a: Row, b: Row): Int = {
+    var i = 0
+    while (i < ordering.size) {
+      val order = ordering(i)
+      val left = order.child.apply(a)
+      val right = order.child.apply(b)
+
+      if (left == null && right == null) {
+        // Both null, continue looking.
+      } else if (left == null) {
+        return if (order.direction == Ascending) -1 else 1
+      } else if (right == null) {
+        return if (order.direction == Ascending) 1 else -1
+      } else {
+        val comparison = order.dataType match {
+          case n: NativeType if order.direction == Ascending =>
+            n.ordering.asInstanceOf[Ordering[Any]].compare(left, right)
+          case n: NativeType if order.direction == Descending =>
+            n.ordering.asInstanceOf[Ordering[Any]].reverse.compare(left, right)
+        }
+        if (comparison != 0) return comparison
+      }
+      i += 1
+    }
+    return 0
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/ScalaUdf.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/ScalaUdf.scala
new file mode 100644
index 0000000000..a3c7ca1acd
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/ScalaUdf.scala
@@ -0,0 +1,41 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import types._
+
+case class ScalaUdf(function: AnyRef, dataType: DataType, children: Seq[Expression])
+  extends Expression {
+
+  type EvaluatedType = Any
+
+  def references = children.flatMap(_.references).toSet
+  def nullable = true
+
+  override def apply(input: Row): Any = {
+    children.size match {
+      case 1 => function.asInstanceOf[(Any) => Any](children(0).apply(input))
+      case 2 =>
+        function.asInstanceOf[(Any, Any) => Any](
+          children(0).apply(input),
+          children(1).apply(input))
+    }
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/SortOrder.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/SortOrder.scala
new file mode 100644
index 0000000000..171997b90e
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/SortOrder.scala
@@ -0,0 +1,34 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+abstract sealed class SortDirection
+case object Ascending extends SortDirection
+case object Descending extends SortDirection
+
+/**
+ * An expression that can be used to sort a tuple.  This class extends expression primarily so that
+ * transformations over expression will descend into its child.
+ */
+case class SortOrder(child: Expression, direction: SortDirection) extends UnaryExpression {
+  def dataType = child.dataType
+  def nullable = child.nullable
+  override def toString = s"$child ${if (direction == Ascending) "ASC" else "DESC"}"
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/WrapDynamic.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/WrapDynamic.scala
new file mode 100644
index 0000000000..2ad8d6f31d
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/WrapDynamic.scala
@@ -0,0 +1,49 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import scala.language.dynamics
+
+import types._
+
+case object DynamicType extends DataType
+
+case class WrapDynamic(children: Seq[Attribute]) extends Expression {
+  type EvaluatedType = DynamicRow
+
+  def nullable = false
+  def references = children.toSet
+  def dataType = DynamicType
+
+  override def apply(input: Row): DynamicRow = input match {
+    // Avoid copy for generic rows.
+    case g: GenericRow => new DynamicRow(children, g.values)
+    case otherRowType => new DynamicRow(children, otherRowType.toArray)
+  }
+}
+
+class DynamicRow(val schema: Seq[Attribute], values: Array[Any])
+  extends GenericRow(values) with Dynamic {
+
+  def selectDynamic(attributeName: String): String = {
+    val ordinal = schema.indexWhere(_.name == attributeName)
+    values(ordinal).toString
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/aggregates.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/aggregates.scala
new file mode 100644
index 0000000000..2287a849e6
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/aggregates.scala
@@ -0,0 +1,265 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import catalyst.types._
+
+abstract class AggregateExpression extends Expression {
+  self: Product =>
+
+  /**
+   * Creates a new instance that can be used to compute this aggregate expression for a group
+   * of input rows/
+   */
+  def newInstance: AggregateFunction
+}
+
+/**
+ * Represents an aggregation that has been rewritten to be performed in two steps.
+ *
+ * @param finalEvaluation an aggregate expression that evaluates to same final result as the
+ *                        original aggregation.
+ * @param partialEvaluations A sequence of [[NamedExpression]]s that can be computed on partial
+ *                           data sets and are required to compute the `finalEvaluation`.
+ */
+case class SplitEvaluation(
+    finalEvaluation: Expression,
+    partialEvaluations: Seq[NamedExpression])
+
+/**
+ * An [[AggregateExpression]] that can be partially computed without seeing all relevent tuples.
+ * These partial evaluations can then be combined to compute the actual answer.
+ */
+abstract class PartialAggregate extends AggregateExpression {
+  self: Product =>
+
+  /**
+   * Returns a [[SplitEvaluation]] that computes this aggregation using partial aggregation.
+   */
+  def asPartial: SplitEvaluation
+}
+
+/**
+ * A specific implementation of an aggregate function. Used to wrap a generic
+ * [[AggregateExpression]] with an algorithm that will be used to compute one specific result.
+ */
+abstract class AggregateFunction
+  extends AggregateExpression with Serializable with trees.LeafNode[Expression] {
+  self: Product =>
+
+  type EvaluatedType = Any
+
+  /** Base should return the generic aggregate expression that this function is computing */
+  val base: AggregateExpression
+  def references = base.references
+  def nullable = base.nullable
+  def dataType = base.dataType
+
+  def update(input: Row): Unit
+  override def apply(input: Row): Any
+
+  // Do we really need this?
+  def newInstance = makeCopy(productIterator.map { case a: AnyRef => a }.toArray)
+}
+
+case class Count(child: Expression) extends PartialAggregate with trees.UnaryNode[Expression] {
+  def references = child.references
+  def nullable = false
+  def dataType = IntegerType
+  override def toString = s"COUNT($child)"
+
+  def asPartial: SplitEvaluation = {
+    val partialCount = Alias(Count(child), "PartialCount")()
+    SplitEvaluation(Sum(partialCount.toAttribute), partialCount :: Nil)
+  }
+
+  override def newInstance = new CountFunction(child, this)
+}
+
+case class CountDistinct(expressions: Seq[Expression]) extends AggregateExpression {
+  def children = expressions
+  def references = expressions.flatMap(_.references).toSet
+  def nullable = false
+  def dataType = IntegerType
+  override def toString = s"COUNT(DISTINCT ${expressions.mkString(",")}})"
+  override def newInstance = new CountDistinctFunction(expressions, this)
+}
+
+case class Average(child: Expression) extends PartialAggregate with trees.UnaryNode[Expression] {
+  def references = child.references
+  def nullable = false
+  def dataType = DoubleType
+  override def toString = s"AVG($child)"
+
+  override def asPartial: SplitEvaluation = {
+    val partialSum = Alias(Sum(child), "PartialSum")()
+    val partialCount = Alias(Count(child), "PartialCount")()
+    val castedSum = Cast(Sum(partialSum.toAttribute), dataType)
+    val castedCount = Cast(Sum(partialCount.toAttribute), dataType)
+
+    SplitEvaluation(
+      Divide(castedSum, castedCount),
+      partialCount :: partialSum :: Nil)
+  }
+
+  override def newInstance = new AverageFunction(child, this)
+}
+
+case class Sum(child: Expression) extends PartialAggregate with trees.UnaryNode[Expression] {
+  def references = child.references
+  def nullable = false
+  def dataType = child.dataType
+  override def toString = s"SUM($child)"
+
+  override def asPartial: SplitEvaluation = {
+    val partialSum = Alias(Sum(child), "PartialSum")()
+    SplitEvaluation(
+      Sum(partialSum.toAttribute),
+      partialSum :: Nil)
+  }
+
+  override def newInstance = new SumFunction(child, this)
+}
+
+case class SumDistinct(child: Expression)
+  extends AggregateExpression with trees.UnaryNode[Expression] {
+
+  def references = child.references
+  def nullable = false
+  def dataType = child.dataType
+  override def toString = s"SUM(DISTINCT $child)"
+
+  override def newInstance = new SumDistinctFunction(child, this)
+}
+
+case class First(child: Expression) extends PartialAggregate with trees.UnaryNode[Expression] {
+  def references = child.references
+  def nullable = child.nullable
+  def dataType = child.dataType
+  override def toString = s"FIRST($child)"
+
+  override def asPartial: SplitEvaluation = {
+    val partialFirst = Alias(First(child), "PartialFirst")()
+    SplitEvaluation(
+      First(partialFirst.toAttribute),
+      partialFirst :: Nil)
+  }
+  override def newInstance = new FirstFunction(child, this)
+}
+
+case class AverageFunction(expr: Expression, base: AggregateExpression)
+  extends AggregateFunction {
+
+  def this() = this(null, null) // Required for serialization.
+
+  private var count: Long = _
+  private val sum = MutableLiteral(Cast(Literal(0), expr.dataType).apply(EmptyRow))
+  private val sumAsDouble = Cast(sum, DoubleType)
+
+
+
+  private val addFunction = Add(sum, expr)
+
+  override def apply(input: Row): Any =
+    sumAsDouble.apply(EmptyRow).asInstanceOf[Double] / count.toDouble
+
+  def update(input: Row): Unit = {
+    count += 1
+    sum.update(addFunction, input)
+  }
+}
+
+case class CountFunction(expr: Expression, base: AggregateExpression) extends AggregateFunction {
+  def this() = this(null, null) // Required for serialization.
+
+  var count: Int = _
+
+  def update(input: Row): Unit = {
+    val evaluatedExpr = expr.map(_.apply(input))
+    if (evaluatedExpr.map(_ != null).reduceLeft(_ || _)) {
+      count += 1
+    }
+  }
+
+  override def apply(input: Row): Any = count
+}
+
+case class SumFunction(expr: Expression, base: AggregateExpression) extends AggregateFunction {
+  def this() = this(null, null) // Required for serialization.
+
+  private val sum = MutableLiteral(Cast(Literal(0), expr.dataType).apply(null))
+
+  private val addFunction = Add(sum, expr)
+
+  def update(input: Row): Unit = {
+    sum.update(addFunction, input)
+  }
+
+  override def apply(input: Row): Any = sum.apply(null)
+}
+
+case class SumDistinctFunction(expr: Expression, base: AggregateExpression)
+  extends AggregateFunction {
+
+  def this() = this(null, null) // Required for serialization.
+
+  val seen = new scala.collection.mutable.HashSet[Any]()
+
+  def update(input: Row): Unit = {
+    val evaluatedExpr = expr.apply(input)
+    if (evaluatedExpr != null) {
+      seen += evaluatedExpr
+    }
+  }
+
+  override def apply(input: Row): Any =
+    seen.reduceLeft(base.dataType.asInstanceOf[NumericType].numeric.asInstanceOf[Numeric[Any]].plus)
+}
+
+case class CountDistinctFunction(expr: Seq[Expression], base: AggregateExpression)
+  extends AggregateFunction {
+
+  def this() = this(null, null) // Required for serialization.
+
+  val seen = new scala.collection.mutable.HashSet[Any]()
+
+  def update(input: Row): Unit = {
+    val evaluatedExpr = expr.map(_.apply(input))
+    if (evaluatedExpr.map(_ != null).reduceLeft(_ && _)) {
+      seen += evaluatedExpr
+    }
+  }
+
+  override def apply(input: Row): Any = seen.size
+}
+
+case class FirstFunction(expr: Expression, base: AggregateExpression) extends AggregateFunction {
+  def this() = this(null, null) // Required for serialization.
+
+  var result: Any = null
+
+  def update(input: Row): Unit = {
+    if (result == null) {
+      result = expr.apply(input)
+    }
+  }
+
+  override def apply(input: Row): Any = result
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/arithmetic.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/arithmetic.scala
new file mode 100644
index 0000000000..db235645cd
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/arithmetic.scala
@@ -0,0 +1,89 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import catalyst.analysis.UnresolvedException
+import catalyst.types._
+
+case class UnaryMinus(child: Expression) extends UnaryExpression {
+  type EvaluatedType = Any
+
+  def dataType = child.dataType
+  override def foldable = child.foldable
+  def nullable = child.nullable
+  override def toString = s"-$child"
+
+  override def apply(input: Row): Any = {
+    n1(child, input, _.negate(_))
+  }
+}
+
+abstract class BinaryArithmetic extends BinaryExpression {
+  self: Product =>
+
+  type EvaluatedType = Any
+
+  def nullable = left.nullable || right.nullable
+
+  override lazy val resolved =
+    left.resolved && right.resolved && left.dataType == right.dataType
+
+  def dataType = {
+    if (!resolved) {
+      throw new UnresolvedException(this,
+        s"datatype. Can not resolve due to differing types ${left.dataType}, ${right.dataType}")
+    }
+    left.dataType
+  }
+}
+
+case class Add(left: Expression, right: Expression) extends BinaryArithmetic {
+  def symbol = "+"
+
+  override def apply(input: Row): Any = n2(input, left, right, _.plus(_, _))
+}
+
+case class Subtract(left: Expression, right: Expression) extends BinaryArithmetic {
+  def symbol = "-"
+
+  override def apply(input: Row): Any = n2(input, left, right, _.minus(_, _))
+}
+
+case class Multiply(left: Expression, right: Expression) extends BinaryArithmetic {
+  def symbol = "*"
+
+  override def apply(input: Row): Any = n2(input, left, right, _.times(_, _))
+}
+
+case class Divide(left: Expression, right: Expression) extends BinaryArithmetic {
+  def symbol = "/"
+
+  override def apply(input: Row): Any = dataType match {
+    case _: FractionalType => f2(input, left, right, _.div(_, _))
+    case _: IntegralType => i2(input, left , right, _.quot(_, _))
+  }
+
+}
+
+case class Remainder(left: Expression, right: Expression) extends BinaryArithmetic {
+  def symbol = "%"
+
+  override def apply(input: Row): Any = i2(input, left, right, _.rem(_, _))
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/complexTypes.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/complexTypes.scala
new file mode 100644
index 0000000000..d3feb6c461
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/complexTypes.scala
@@ -0,0 +1,96 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import types._
+
+/**
+ * Returns the item at `ordinal` in the Array `child` or the Key `ordinal` in Map `child`.
+ */
+case class GetItem(child: Expression, ordinal: Expression) extends Expression {
+  type EvaluatedType = Any
+
+  val children = child :: ordinal :: Nil
+  /** `Null` is returned for invalid ordinals. */
+  override def nullable = true
+  override def references = children.flatMap(_.references).toSet
+  def dataType = child.dataType match {
+    case ArrayType(dt) => dt
+    case MapType(_, vt) => vt
+  }
+  override lazy val resolved =
+    childrenResolved &&
+    (child.dataType.isInstanceOf[ArrayType] || child.dataType.isInstanceOf[MapType])
+
+  override def toString = s"$child[$ordinal]"
+
+  override def apply(input: Row): Any = {
+    if (child.dataType.isInstanceOf[ArrayType]) {
+      val baseValue = child.apply(input).asInstanceOf[Seq[_]]
+      val o = ordinal.apply(input).asInstanceOf[Int]
+      if (baseValue == null) {
+        null
+      } else if (o >= baseValue.size || o < 0) {
+        null
+      } else {
+        baseValue(o)
+      }
+    } else {
+      val baseValue = child.apply(input).asInstanceOf[Map[Any, _]]
+      val key = ordinal.apply(input)
+      if (baseValue == null) {
+        null
+      } else {
+        baseValue.get(key).orNull
+      }
+    }
+  }
+}
+
+/**
+ * Returns the value of fields in the Struct `child`.
+ */
+case class GetField(child: Expression, fieldName: String) extends UnaryExpression {
+  type EvaluatedType = Any
+
+  def dataType = field.dataType
+  def nullable = field.nullable
+
+  protected def structType = child.dataType match {
+    case s: StructType => s
+    case otherType => sys.error(s"GetField is not valid on fields of type $otherType")
+  }
+
+  lazy val field =
+    structType.fields
+        .find(_.name == fieldName)
+        .getOrElse(sys.error(s"No such field $fieldName in ${child.dataType}"))
+
+  lazy val ordinal = structType.fields.indexOf(field)
+
+  override lazy val resolved = childrenResolved && child.dataType.isInstanceOf[StructType]
+
+  override def apply(input: Row): Any = {
+    val baseValue = child.apply(input).asInstanceOf[Row]
+    if (baseValue == null) null else baseValue(ordinal)
+  }
+
+  override def toString = s"$child.$fieldName"
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/generators.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/generators.scala
new file mode 100644
index 0000000000..c367de2a3e
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/generators.scala
@@ -0,0 +1,116 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import catalyst.types._
+
+/**
+ * An expression that produces zero or more rows given a single input row.
+ *
+ * Generators produce multiple output rows instead of a single value like other expressions,
+ * and thus they must have a schema to associate with the rows that are output.
+ *
+ * However, unlike row producing relational operators, which are either leaves or determine their
+ * output schema functionally from their input, generators can contain other expressions that
+ * might result in their modification by rules.  This structure means that they might be copied
+ * multiple times after first determining their output schema. If a new output schema is created for
+ * each copy references up the tree might be rendered invalid. As a result generators must
+ * instead define a function `makeOutput` which is called only once when the schema is first
+ * requested.  The attributes produced by this function will be automatically copied anytime rules
+ * result in changes to the Generator or its children.
+ */
+abstract class Generator extends Expression with (Row => TraversableOnce[Row]) {
+  self: Product =>
+
+  type EvaluatedType = TraversableOnce[Row]
+
+  lazy val dataType =
+    ArrayType(StructType(output.map(a => StructField(a.name, a.dataType, a.nullable))))
+
+  def nullable = false
+
+  def references = children.flatMap(_.references).toSet
+
+  /**
+   * Should be overridden by specific generators.  Called only once for each instance to ensure
+   * that rule application does not change the output schema of a generator.
+   */
+  protected def makeOutput(): Seq[Attribute]
+
+  private var _output: Seq[Attribute] = null
+
+  def output: Seq[Attribute] = {
+    if (_output == null) {
+      _output = makeOutput()
+    }
+    _output
+  }
+
+  /** Should be implemented by child classes to perform specific Generators. */
+  def apply(input: Row): TraversableOnce[Row]
+
+  /** Overridden `makeCopy` also copies the attributes that are produced by this generator. */
+  override def makeCopy(newArgs: Array[AnyRef]): this.type = {
+    val copy = super.makeCopy(newArgs)
+    copy._output = _output
+    copy
+  }
+}
+
+/**
+ * Given an input array produces a sequence of rows for each value in the array.
+ */
+case class Explode(attributeNames: Seq[String], child: Expression)
+  extends Generator with trees.UnaryNode[Expression] {
+
+  override lazy val resolved =
+    child.resolved &&
+    (child.dataType.isInstanceOf[ArrayType] || child.dataType.isInstanceOf[MapType])
+
+  lazy val elementTypes = child.dataType match {
+    case ArrayType(et) => et :: Nil
+    case MapType(kt,vt) => kt :: vt :: Nil
+  }
+
+  // TODO: Move this pattern into Generator.
+  protected def makeOutput() =
+    if (attributeNames.size == elementTypes.size) {
+      attributeNames.zip(elementTypes).map {
+        case (n, t) => AttributeReference(n, t, nullable = true)()
+      }
+    } else {
+      elementTypes.zipWithIndex.map {
+        case (t, i) => AttributeReference(s"c_$i", t, nullable = true)()
+      }
+    }
+
+  override def apply(input: Row): TraversableOnce[Row] = {
+    child.dataType match {
+      case ArrayType(_) =>
+        val inputArray = child.apply(input).asInstanceOf[Seq[Any]]
+        if (inputArray == null) Nil else inputArray.map(v => new GenericRow(Array(v)))
+      case MapType(_, _) =>
+        val inputMap = child.apply(input).asInstanceOf[Map[Any,Any]]
+        if (inputMap == null) Nil else inputMap.map { case (k,v) => new GenericRow(Array(k,v)) }
+    }
+  }
+
+  override def toString() = s"explode($child)"
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/literals.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/literals.scala
new file mode 100644
index 0000000000..229d8f7f7b
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/literals.scala
@@ -0,0 +1,73 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import types._
+
+object Literal {
+  def apply(v: Any): Literal = v match {
+    case i: Int => Literal(i, IntegerType)
+    case l: Long => Literal(l, LongType)
+    case d: Double => Literal(d, DoubleType)
+    case f: Float => Literal(f, FloatType)
+    case b: Byte => Literal(b, ByteType)
+    case s: Short => Literal(s, ShortType)
+    case s: String => Literal(s, StringType)
+    case b: Boolean => Literal(b, BooleanType)
+    case null => Literal(null, NullType)
+  }
+}
+
+/**
+ * Extractor for retrieving Int literals.
+ */
+object IntegerLiteral {
+  def unapply(a: Any): Option[Int] = a match {
+    case Literal(a: Int, IntegerType) => Some(a)
+    case _ => None
+  }
+}
+
+case class Literal(value: Any, dataType: DataType) extends LeafExpression {
+
+  override def foldable = true
+  def nullable = value == null
+  def references = Set.empty
+
+  override def toString = if (value != null) value.toString else "null"
+
+  type EvaluatedType = Any
+  override def apply(input: Row):Any = value
+}
+
+// TODO: Specialize
+case class MutableLiteral(var value: Any, nullable: Boolean = true) extends LeafExpression {
+  type EvaluatedType = Any
+
+  val dataType = Literal(value).dataType
+
+  def references = Set.empty
+
+  def update(expression: Expression, input: Row) = {
+    value = expression.apply(input)
+  }
+
+  override def apply(input: Row) = value
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/namedExpressions.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/namedExpressions.scala
new file mode 100644
index 0000000000..0a06e85325
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/namedExpressions.scala
@@ -0,0 +1,156 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import catalyst.analysis.UnresolvedAttribute
+import types._
+
+object NamedExpression {
+  private val curId = new java.util.concurrent.atomic.AtomicLong()
+  def newExprId = ExprId(curId.getAndIncrement())
+}
+
+/**
+ * A globally (within this JVM) id for a given named expression.
+ * Used to identify with attribute output by a relation is being
+ * referenced in a subsuqent computation.
+ */
+case class ExprId(id: Long)
+
+abstract class NamedExpression extends Expression {
+  self: Product =>
+
+  def name: String
+  def exprId: ExprId
+  def qualifiers: Seq[String]
+
+  def toAttribute: Attribute
+
+  protected def typeSuffix =
+    if (resolved) {
+      dataType match {
+        case LongType => "L"
+        case _ => ""
+      }
+    } else {
+      ""
+    }
+}
+
+abstract class Attribute extends NamedExpression {
+  self: Product =>
+
+  def withQualifiers(newQualifiers: Seq[String]): Attribute
+
+  def references = Set(this)
+  def toAttribute = this
+  def newInstance: Attribute
+}
+
+/**
+ * Used to assign a new name to a computation.
+ * For example the SQL expression "1 + 1 AS a" could be represented as follows:
+ *  Alias(Add(Literal(1), Literal(1), "a")()
+ *
+ * @param child the computation being performed
+ * @param name the name to be associated with the result of computing [[child]].
+ * @param exprId A globally unique id used to check if an [[AttributeReference]] refers to this
+ *               alias. Auto-assigned if left blank.
+ */
+case class Alias(child: Expression, name: String)
+    (val exprId: ExprId = NamedExpression.newExprId, val qualifiers: Seq[String] = Nil)
+  extends NamedExpression with trees.UnaryNode[Expression] {
+
+  type EvaluatedType = Any
+
+  override def apply(input: Row) = child.apply(input)
+
+  def dataType = child.dataType
+  def nullable = child.nullable
+  def references = child.references
+
+  def toAttribute = {
+    if (resolved) {
+      AttributeReference(name, child.dataType, child.nullable)(exprId, qualifiers)
+    } else {
+      UnresolvedAttribute(name)
+    }
+  }
+
+  override def toString: String = s"$child AS $name#${exprId.id}$typeSuffix"
+
+  override protected final def otherCopyArgs = exprId :: qualifiers :: Nil
+}
+
+/**
+ * A reference to an attribute produced by another operator in the tree.
+ *
+ * @param name The name of this attribute, should only be used during analysis or for debugging.
+ * @param dataType The [[types.DataType DataType]] of this attribute.
+ * @param nullable True if null is a valid value for this attribute.
+ * @param exprId A globally unique id used to check if different AttributeReferences refer to the
+ *               same attribute.
+ * @param qualifiers a list of strings that can be used to referred to this attribute in a fully
+ *                   qualified way. Consider the examples tableName.name, subQueryAlias.name.
+ *                   tableName and subQueryAlias are possible qualifiers.
+ */
+case class AttributeReference(name: String, dataType: DataType, nullable: Boolean = true)
+    (val exprId: ExprId = NamedExpression.newExprId, val qualifiers: Seq[String] = Nil)
+  extends Attribute with trees.LeafNode[Expression] {
+
+  override def equals(other: Any) = other match {
+    case ar: AttributeReference => exprId == ar.exprId && dataType == ar.dataType
+    case _ => false
+  }
+
+  override def hashCode: Int = {
+    // See http://stackoverflow.com/questions/113511/hash-code-implementation
+    var h = 17
+    h = h * 37 + exprId.hashCode()
+    h = h * 37 + dataType.hashCode()
+    h
+  }
+
+  def newInstance = AttributeReference(name, dataType, nullable)(qualifiers = qualifiers)
+
+  /**
+   * Returns a copy of this [[AttributeReference]] with changed nullability.
+   */
+  def withNullability(newNullability: Boolean) = {
+    if (nullable == newNullability) {
+      this
+    } else {
+      AttributeReference(name, dataType, newNullability)(exprId, qualifiers)
+    }
+  }
+
+  /**
+   * Returns a copy of this [[AttributeReference]] with new qualifiers.
+   */
+  def withQualifiers(newQualifiers: Seq[String]) = {
+    if (newQualifiers == qualifiers) {
+      this
+    } else {
+      AttributeReference(name, dataType, nullable)(exprId, newQualifiers)
+    }
+  }
+
+  override def toString: String = s"$name#${exprId.id}$typeSuffix"
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/nullFunctions.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/nullFunctions.scala
new file mode 100644
index 0000000000..e869a4d9b0
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/nullFunctions.scala
@@ -0,0 +1,75 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import catalyst.analysis.UnresolvedException
+
+case class Coalesce(children: Seq[Expression]) extends Expression {
+  type EvaluatedType = Any
+
+  /** Coalesce is nullable if all of its children are nullable, or if it has no children. */
+  def nullable = !children.exists(!_.nullable)
+
+  def references = children.flatMap(_.references).toSet
+  // Coalesce is foldable if all children are foldable.
+  override def foldable = !children.exists(!_.foldable)
+
+  // Only resolved if all the children are of the same type.
+  override lazy val resolved = childrenResolved && (children.map(_.dataType).distinct.size == 1)
+
+  override def toString = s"Coalesce(${children.mkString(",")})"
+
+  def dataType = if (resolved) {
+    children.head.dataType
+  } else {
+    throw new UnresolvedException(this, "Coalesce cannot have children of different types.")
+  }
+
+  override def apply(input: Row): Any = {
+    var i = 0
+    var result: Any = null
+    while(i < children.size && result == null) {
+      result = children(i).apply(input)
+      i += 1
+    }
+    result
+  }
+}
+
+case class IsNull(child: Expression) extends Predicate with trees.UnaryNode[Expression] {
+  def references = child.references
+  override def foldable = child.foldable
+  def nullable = false
+
+  override def apply(input: Row): Any = {
+    child.apply(input) == null
+  }
+}
+
+case class IsNotNull(child: Expression) extends Predicate with trees.UnaryNode[Expression] {
+  def references = child.references
+  override def foldable = child.foldable
+  def nullable = false
+  override def toString = s"IS NOT NULL $child"
+
+  override def apply(input: Row): Any = {
+    child.apply(input) != null
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/package.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/package.scala
new file mode 100644
index 0000000000..76554e160b
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/package.scala
@@ -0,0 +1,51 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+
+/**
+ * A set of classes that can be used to represent trees of relational expressions.  A key goal of
+ * the expression library is to hide the details of naming and scoping from developers who want to
+ * manipulate trees of relational operators. As such, the library defines a special type of
+ * expression, a [[NamedExpression]] in addition to the standard collection of expressions.
+ *
+ * ==Standard Expressions==
+ * A library of standard expressions (e.g., [[Add]], [[Equals]]), aggregates (e.g., SUM, COUNT),
+ * and other computations (e.g. UDFs). Each expression type is capable of determining its output
+ * schema as a function of its children's output schema.
+ *
+ * ==Named Expressions==
+ * Some expression are named and thus can be referenced by later operators in the dataflow graph.
+ * The two types of named expressions are [[AttributeReference]]s and [[Alias]]es.
+ * [[AttributeReference]]s refer to attributes of the input tuple for a given operator and form
+ * the leaves of some expression trees.  Aliases assign a name to intermediate computations.
+ * For example, in the SQL statement `SELECT a+b AS c FROM ...`, the expressions `a` and `b` would
+ * be represented by `AttributeReferences` and `c` would be represented by an `Alias`.
+ *
+ * During [[analysis]], all named expressions are assigned a globally unique expression id, which
+ * can be used for equality comparisons.  While the original names are kept around for debugging
+ * purposes, they should never be used to check if two attributes refer to the same value, as
+ * plan transformations can result in the introduction of naming ambiguity. For example, consider
+ * a plan that contains subqueries, both of which are reading from the same table.  If an
+ * optimization removes the subqueries, scoping information would be destroyed, eliminating the
+ * ability to reason about which subquery produced a given attribute.
+ *
+ * ==Evaluation==
+ * The result of expressions can be evaluated using the [[Evaluate]] object.
+ */
+package object expressions
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/predicates.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/predicates.scala
new file mode 100644
index 0000000000..561396eb43
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/predicates.scala
@@ -0,0 +1,213 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import types._
+import catalyst.analysis.UnresolvedException
+
+trait Predicate extends Expression {
+  self: Product =>
+
+  def dataType = BooleanType
+
+  type EvaluatedType = Any
+}
+
+trait PredicateHelper {
+  def splitConjunctivePredicates(condition: Expression): Seq[Expression] = condition match {
+    case And(cond1, cond2) => splitConjunctivePredicates(cond1) ++ splitConjunctivePredicates(cond2)
+    case other => other :: Nil
+  }
+}
+
+abstract class BinaryPredicate extends BinaryExpression with Predicate {
+  self: Product =>
+  def nullable = left.nullable || right.nullable
+}
+
+case class Not(child: Expression) extends Predicate with trees.UnaryNode[Expression] {
+  def references = child.references
+  override def foldable = child.foldable
+  def nullable = child.nullable
+  override def toString = s"NOT $child"
+
+  override def apply(input: Row): Any = {
+    child.apply(input) match {
+      case null => null
+      case b: Boolean => !b
+    }
+  }
+}
+
+/**
+ * Evaluates to `true` if `list` contains `value`.
+ */
+case class In(value: Expression, list: Seq[Expression]) extends Predicate {
+  def children = value +: list
+  def references = children.flatMap(_.references).toSet
+  def nullable = true // TODO: Figure out correct nullability semantics of IN.
+  override def toString = s"$value IN ${list.mkString("(", ",", ")")}"
+
+  override def apply(input: Row): Any = {
+    val evaluatedValue = value.apply(input)
+    list.exists(e => e.apply(input) == evaluatedValue)
+  }
+}
+
+case class And(left: Expression, right: Expression) extends BinaryPredicate {
+  def symbol = "&&"
+
+  override def apply(input: Row): Any = {
+    val l = left.apply(input)
+    val r = right.apply(input)
+    if (l == false || r == false) {
+      false
+    } else if (l == null || r == null ) {
+      null
+    } else {
+      true
+    }
+  }
+}
+
+case class Or(left: Expression, right: Expression) extends BinaryPredicate {
+  def symbol = "||"
+
+  override def apply(input: Row): Any = {
+    val l = left.apply(input)
+    val r = right.apply(input)
+    if (l == true || r == true) {
+      true
+    } else if (l == null || r == null) {
+      null
+    } else {
+      false
+    }
+  }
+}
+
+abstract class BinaryComparison extends BinaryPredicate {
+  self: Product =>
+}
+
+case class Equals(left: Expression, right: Expression) extends BinaryComparison {
+  def symbol = "="
+  override def apply(input: Row): Any = {
+    val l = left.apply(input)
+    val r = right.apply(input)
+    if (l == null || r == null) null else l == r
+  }
+}
+
+case class LessThan(left: Expression, right: Expression) extends BinaryComparison {
+  def symbol = "<"
+  override def apply(input: Row): Any = {
+    if (left.dataType == StringType && right.dataType == StringType) {
+      val l = left.apply(input)
+      val r = right.apply(input)
+      if(l == null || r == null) {
+        null
+      } else {
+        l.asInstanceOf[String] < r.asInstanceOf[String]
+      }
+    } else {
+      n2(input, left, right, _.lt(_, _))
+    }
+  }
+}
+
+case class LessThanOrEqual(left: Expression, right: Expression) extends BinaryComparison {
+  def symbol = "<="
+  override def apply(input: Row): Any = {
+    if (left.dataType == StringType && right.dataType == StringType) {
+      val l = left.apply(input)
+      val r = right.apply(input)
+      if(l == null || r == null) {
+        null
+      } else {
+        l.asInstanceOf[String] <= r.asInstanceOf[String]
+      }
+    } else {
+      n2(input, left, right, _.lteq(_, _))
+    }
+  }
+}
+
+case class GreaterThan(left: Expression, right: Expression) extends BinaryComparison {
+  def symbol = ">"
+  override def apply(input: Row): Any = {
+    if (left.dataType == StringType && right.dataType == StringType) {
+      val l = left.apply(input)
+      val r = right.apply(input)
+      if(l == null || r == null) {
+        null
+      } else {
+        l.asInstanceOf[String] > r.asInstanceOf[String]
+      }
+    } else {
+      n2(input, left, right, _.gt(_, _))
+    }
+  }
+}
+
+case class GreaterThanOrEqual(left: Expression, right: Expression) extends BinaryComparison {
+  def symbol = ">="
+  override def apply(input: Row): Any = {
+    if (left.dataType == StringType && right.dataType == StringType) {
+      val l = left.apply(input)
+      val r = right.apply(input)
+      if(l == null || r == null) {
+        null
+      } else {
+        l.asInstanceOf[String] >= r.asInstanceOf[String]
+      }
+    } else {
+      n2(input, left, right, _.gteq(_, _))
+    }
+  }
+}
+
+case class If(predicate: Expression, trueValue: Expression, falseValue: Expression)
+    extends Expression {
+
+  def children = predicate :: trueValue :: falseValue :: Nil
+  def nullable = trueValue.nullable || falseValue.nullable
+  def references = children.flatMap(_.references).toSet
+  override lazy val resolved = childrenResolved && trueValue.dataType == falseValue.dataType
+  def dataType = {
+    if (!resolved) {
+      throw new UnresolvedException(
+        this,
+        s"Can not resolve due to differing types ${trueValue.dataType}, ${falseValue.dataType}")
+    }
+    trueValue.dataType
+  }
+
+  type EvaluatedType = Any
+  override def apply(input: Row): Any = {
+    if (predicate(input).asInstanceOf[Boolean]) {
+      trueValue.apply(input)
+    } else {
+      falseValue.apply(input)
+    }
+  }
+
+  override def toString = s"if ($predicate) $trueValue else $falseValue"
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/stringOperations.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/stringOperations.scala
new file mode 100644
index 0000000000..6e585236b1
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/stringOperations.scala
@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import catalyst.types.BooleanType
+
+case class Like(left: Expression, right: Expression) extends BinaryExpression {
+  def dataType = BooleanType
+  def nullable = left.nullable // Right cannot be null.
+  def symbol = "LIKE"
+}
+
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/Optimizer.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/Optimizer.scala
new file mode 100644
index 0000000000..4db2803173
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/Optimizer.scala
@@ -0,0 +1,167 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package optimizer
+
+import catalyst.expressions._
+import catalyst.plans.logical._
+import catalyst.rules._
+import catalyst.types.BooleanType
+import catalyst.plans.Inner
+
+object Optimizer extends RuleExecutor[LogicalPlan] {
+  val batches =
+    Batch("Subqueries", Once,
+      EliminateSubqueries) ::
+    Batch("ConstantFolding", Once,
+      ConstantFolding,
+      BooleanSimplification,
+      SimplifyCasts) ::
+    Batch("Filter Pushdown", Once,
+      EliminateSubqueries,
+      CombineFilters,
+      PushPredicateThroughProject,
+      PushPredicateThroughInnerJoin) :: Nil
+}
+
+/**
+ * Removes [[catalyst.plans.logical.Subquery Subquery]] operators from the plan.  Subqueries are
+ * only required to provide scoping information for attributes and can be removed once analysis is
+ * complete.
+ */
+object EliminateSubqueries extends Rule[LogicalPlan] {
+  def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+    case Subquery(_, child) => child
+  }
+}
+
+/**
+ * Replaces [[catalyst.expressions.Expression Expressions]] that can be statically evaluated with
+ * equivalent [[catalyst.expressions.Literal Literal]] values.
+ */
+object ConstantFolding extends Rule[LogicalPlan] {
+  def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+    case q: LogicalPlan => q transformExpressionsDown {
+      // Skip redundant folding of literals.
+      case l: Literal => l
+      case e if e.foldable => Literal(e.apply(null), e.dataType)
+    }
+  }
+}
+
+/**
+ * Simplifies boolean expressions where the answer can be determined without evaluating both sides.
+ * Note that this rule can eliminate expressions that might otherwise have been evaluated and thus
+ * is only safe when evaluations of expressions does not result in side effects.
+ */
+object BooleanSimplification extends Rule[LogicalPlan] {
+  def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+    case q: LogicalPlan => q transformExpressionsUp {
+      case and @ And(left, right) => {
+        (left, right) match {
+          case (Literal(true, BooleanType), r) => r
+          case (l, Literal(true, BooleanType)) => l
+          case (Literal(false, BooleanType), _) => Literal(false)
+          case (_, Literal(false, BooleanType)) => Literal(false)
+          case (_, _) => and
+        }
+      }
+      case or @ Or(left, right) => {
+        (left, right) match {
+          case (Literal(true, BooleanType), _) => Literal(true)
+          case (_, Literal(true, BooleanType)) => Literal(true)
+          case (Literal(false, BooleanType), r) => r
+          case (l, Literal(false, BooleanType)) => l
+          case (_, _) => or
+        }
+      }
+    }
+  }
+}
+
+/**
+ * Combines two adjacent [[catalyst.plans.logical.Filter Filter]] operators into one, merging the
+ * conditions into one conjunctive predicate.
+ */
+object CombineFilters extends Rule[LogicalPlan] {
+  def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+    case ff@Filter(fc, nf@Filter(nc, grandChild)) => Filter(And(nc, fc), grandChild)
+  }
+}
+
+/**
+ * Pushes [[catalyst.plans.logical.Filter Filter]] operators through
+ * [[catalyst.plans.logical.Project Project]] operators, in-lining any
+ * [[catalyst.expressions.Alias Aliases]] that were defined in the projection.
+ *
+ * This heuristic is valid assuming the expression evaluation cost is minimal.
+ */
+object PushPredicateThroughProject extends Rule[LogicalPlan] {
+  def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+    case filter@Filter(condition, project@Project(fields, grandChild)) =>
+      val sourceAliases = fields.collect { case a@Alias(c, _) => a.toAttribute -> c }.toMap
+      project.copy(child = filter.copy(
+        replaceAlias(condition, sourceAliases),
+        grandChild))
+  }
+
+  //
+  def replaceAlias(condition: Expression, sourceAliases: Map[Attribute, Expression]): Expression = {
+    condition transform {
+      case a: AttributeReference => sourceAliases.getOrElse(a, a)
+    }
+  }
+}
+
+/**
+ * Pushes down [[catalyst.plans.logical.Filter Filter]] operators where the `condition` can be
+ * evaluated using only the attributes of the left or right side of an inner join.  Other
+ * [[catalyst.plans.logical.Filter Filter]] conditions are moved into the `condition` of the
+ * [[catalyst.plans.logical.Join Join]].
+ */
+object PushPredicateThroughInnerJoin extends Rule[LogicalPlan] with PredicateHelper {
+  def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+    case f @ Filter(filterCondition, Join(left, right, Inner, joinCondition)) =>
+      val allConditions =
+        splitConjunctivePredicates(filterCondition) ++
+          joinCondition.map(splitConjunctivePredicates).getOrElse(Nil)
+
+      // Split the predicates into those that can be evaluated on the left, right, and those that
+      // must be evaluated after the join.
+      val (rightConditions, leftOrJoinConditions) =
+        allConditions.partition(_.references subsetOf right.outputSet)
+      val (leftConditions, joinConditions) =
+        leftOrJoinConditions.partition(_.references subsetOf left.outputSet)
+
+      // Build the new left and right side, optionally with the pushed down filters.
+      val newLeft = leftConditions.reduceLeftOption(And).map(Filter(_, left)).getOrElse(left)
+      val newRight = rightConditions.reduceLeftOption(And).map(Filter(_, right)).getOrElse(right)
+      Join(newLeft, newRight, Inner, joinConditions.reduceLeftOption(And))
+  }
+}
+
+/**
+ * Removes [[catalyst.expressions.Cast Casts]] that are unnecessary because the input is already
+ * the correct type.
+ */
+object SimplifyCasts extends Rule[LogicalPlan] {
+  def apply(plan: LogicalPlan): LogicalPlan = plan transformAllExpressions {
+    case Cast(e, dataType) if e.dataType == dataType => e
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/planning/QueryPlanner.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/planning/QueryPlanner.scala
new file mode 100644
index 0000000000..22f8ea005b
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/planning/QueryPlanner.scala
@@ -0,0 +1,64 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package planning
+
+
+import plans.logical.LogicalPlan
+import trees._
+
+/**
+ * Abstract class for transforming [[plans.logical.LogicalPlan LogicalPlan]]s into physical plans.
+ * Child classes are responsible for specifying a list of [[Strategy]] objects that each of which
+ * can return a list of possible physical plan options.  If a given strategy is unable to plan all
+ * of the remaining operators in the tree, it can call [[planLater]], which returns a placeholder
+ * object that will be filled in using other available strategies.
+ *
+ * TODO: RIGHT NOW ONLY ONE PLAN IS RETURNED EVER...
+ *       PLAN SPACE EXPLORATION WILL BE IMPLEMENTED LATER.
+ *
+ * @tparam PhysicalPlan The type of physical plan produced by this [[QueryPlanner]]
+ */
+abstract class QueryPlanner[PhysicalPlan <: TreeNode[PhysicalPlan]] {
+  /** A list of execution strategies that can be used by the planner */
+  def strategies: Seq[Strategy]
+
+  /**
+   * Given a [[plans.logical.LogicalPlan LogicalPlan]], returns a list of `PhysicalPlan`s that can
+   * be used for execution. If this strategy does not apply to the give logical operation then an
+   * empty list should be returned.
+   */
+  abstract protected class Strategy extends Logging {
+    def apply(plan: LogicalPlan): Seq[PhysicalPlan]
+  }
+
+  /**
+   * Returns a placeholder for a physical plan that executes `plan`. This placeholder will be
+   * filled in automatically by the QueryPlanner using the other execution strategies that are
+   * available.
+   */
+  protected def planLater(plan: LogicalPlan) = apply(plan).next()
+
+  def apply(plan: LogicalPlan): Iterator[PhysicalPlan] = {
+    // Obviously a lot to do here still...
+    val iter = strategies.view.flatMap(_(plan)).toIterator
+    assert(iter.hasNext, s"No plan for $plan")
+    iter
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/planning/package.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/planning/package.scala
new file mode 100644
index 0000000000..64370ec7c0
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/planning/package.scala
@@ -0,0 +1,24 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+
+/**
+ * Contains classes for enumerating possible physical plans for a given logical query plan.
+ */
+package object planning
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/planning/patterns.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/planning/patterns.scala
new file mode 100644
index 0000000000..613b028ca8
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/planning/patterns.scala
@@ -0,0 +1,117 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package planning
+
+import scala.annotation.tailrec
+
+import expressions._
+import plans.logical._
+
+/**
+ * A pattern that matches any number of filter operations on top of another relational operator.
+ * Adjacent filter operators are collected and their conditions are broken up and returned as a
+ * sequence of conjunctive predicates.
+ *
+ * @return A tuple containing a sequence of conjunctive predicates that should be used to filter the
+ *         output and a relational operator.
+ */
+object FilteredOperation extends PredicateHelper {
+  type ReturnType = (Seq[Expression], LogicalPlan)
+
+  def unapply(plan: LogicalPlan): Option[ReturnType] = Some(collectFilters(Nil, plan))
+
+  @tailrec
+  private def collectFilters(filters: Seq[Expression], plan: LogicalPlan): ReturnType = plan match {
+    case Filter(condition, child) =>
+      collectFilters(filters ++ splitConjunctivePredicates(condition), child)
+    case other => (filters, other)
+  }
+}
+
+/**
+ * A pattern that matches any number of project or filter operations on top of another relational
+ * operator.  All filter operators are collected and their conditions are broken up and returned
+ * together with the top project operator.  [[Alias Aliases]] are in-lined/substituted if necessary.
+ */
+object PhysicalOperation extends PredicateHelper {
+  type ReturnType = (Seq[NamedExpression], Seq[Expression], LogicalPlan)
+
+  def unapply(plan: LogicalPlan): Option[ReturnType] = {
+    val (fields, filters, child, _) = collectProjectsAndFilters(plan)
+    Some((fields.getOrElse(child.output), filters, child))
+  }
+
+  /**
+   * Collects projects and filters, in-lining/substituting aliases if necessary.  Here are two
+   * examples for alias in-lining/substitution.  Before:
+   * {{{
+   *   SELECT c1 FROM (SELECT key AS c1 FROM t1) t2 WHERE c1 > 10
+   *   SELECT c1 AS c2 FROM (SELECT key AS c1 FROM t1) t2 WHERE c1 > 10
+   * }}}
+   * After:
+   * {{{
+   *   SELECT key AS c1 FROM t1 WHERE key > 10
+   *   SELECT key AS c2 FROM t1 WHERE key > 10
+   * }}}
+   */
+  def collectProjectsAndFilters(plan: LogicalPlan):
+      (Option[Seq[NamedExpression]], Seq[Expression], LogicalPlan, Map[Attribute, Expression]) =
+    plan match {
+      case Project(fields, child) =>
+        val (_, filters, other, aliases) = collectProjectsAndFilters(child)
+        val substitutedFields = fields.map(substitute(aliases)).asInstanceOf[Seq[NamedExpression]]
+        (Some(substitutedFields), filters, other, collectAliases(substitutedFields))
+
+      case Filter(condition, child) =>
+        val (fields, filters, other, aliases) = collectProjectsAndFilters(child)
+        val substitutedCondition = substitute(aliases)(condition)
+        (fields, filters ++ splitConjunctivePredicates(substitutedCondition), other, aliases)
+
+      case other =>
+        (None, Nil, other, Map.empty)
+    }
+
+  def collectAliases(fields: Seq[Expression]) = fields.collect {
+    case a @ Alias(child, _) => a.toAttribute.asInstanceOf[Attribute] -> child
+  }.toMap
+
+  def substitute(aliases: Map[Attribute, Expression])(expr: Expression) = expr.transform {
+    case a @ Alias(ref: AttributeReference, name) =>
+      aliases.get(ref).map(Alias(_, name)(a.exprId, a.qualifiers)).getOrElse(a)
+
+    case a: AttributeReference =>
+      aliases.get(a).map(Alias(_, a.name)(a.exprId, a.qualifiers)).getOrElse(a)
+  }
+}
+
+/**
+ * A pattern that collects all adjacent unions and returns their children as a Seq.
+ */
+object Unions {
+  def unapply(plan: LogicalPlan): Option[Seq[LogicalPlan]] = plan match {
+    case u: Union => Some(collectUnionChildren(u))
+    case _ => None
+  }
+
+  private def collectUnionChildren(plan: LogicalPlan): Seq[LogicalPlan] = plan match {
+    case Union(l, r) => collectUnionChildren(l) ++ collectUnionChildren(r)
+    case other => other :: Nil
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/QueryPlan.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/QueryPlan.scala
new file mode 100644
index 0000000000..20f230c5c4
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/QueryPlan.scala
@@ -0,0 +1,128 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package plans
+
+import catalyst.expressions.{SortOrder, Attribute, Expression}
+import catalyst.trees._
+
+abstract class QueryPlan[PlanType <: TreeNode[PlanType]] extends TreeNode[PlanType] {
+  self: PlanType with Product =>
+
+  def output: Seq[Attribute]
+
+  /**
+   * Returns the set of attributes that are output by this node.
+   */
+  def outputSet: Set[Attribute] = output.toSet
+
+  /**
+   * Runs [[transform]] with `rule` on all expressions present in this query operator.
+   * Users should not expect a specific directionality. If a specific directionality is needed,
+   * transformExpressionsDown or transformExpressionsUp should be used.
+   * @param rule the rule to be applied to every expression in this operator.
+   */
+  def transformExpressions(rule: PartialFunction[Expression, Expression]): this.type = {
+    transformExpressionsDown(rule)
+  }
+
+  /**
+   * Runs [[transformDown]] with `rule` on all expressions present in this query operator.
+   * @param rule the rule to be applied to every expression in this operator.
+   */
+  def transformExpressionsDown(rule: PartialFunction[Expression, Expression]): this.type = {
+    var changed = false
+
+    @inline def transformExpressionDown(e: Expression) = {
+      val newE = e.transformDown(rule)
+      if (newE.id != e.id && newE != e) {
+        changed = true
+        newE
+      } else {
+        e
+      }
+    }
+
+    val newArgs = productIterator.map {
+      case e: Expression => transformExpressionDown(e)
+      case Some(e: Expression) => Some(transformExpressionDown(e))
+      case m: Map[_,_] => m
+      case seq: Traversable[_] => seq.map {
+        case e: Expression => transformExpressionDown(e)
+        case other => other
+      }
+      case other: AnyRef => other
+    }.toArray
+
+    if (changed) makeCopy(newArgs) else this
+  }
+
+  /**
+   * Runs [[transformUp]] with `rule` on all expressions present in this query operator.
+   * @param rule the rule to be applied to every expression in this operator.
+   * @return
+   */
+  def transformExpressionsUp(rule: PartialFunction[Expression, Expression]): this.type = {
+    var changed = false
+
+    @inline def transformExpressionUp(e: Expression) = {
+      val newE = e.transformUp(rule)
+      if (newE.id != e.id && newE != e) {
+        changed = true
+        newE
+      } else {
+        e
+      }
+    }
+
+    val newArgs = productIterator.map {
+      case e: Expression => transformExpressionUp(e)
+      case Some(e: Expression) => Some(transformExpressionUp(e))
+      case m: Map[_,_] => m
+      case seq: Traversable[_] => seq.map {
+        case e: Expression => transformExpressionUp(e)
+        case other => other
+      }
+      case other: AnyRef => other
+    }.toArray
+
+    if (changed) makeCopy(newArgs) else this
+  }
+
+  /** Returns the result of running [[transformExpressions]] on this node
+    * and all its children. */
+  def transformAllExpressions(rule: PartialFunction[Expression, Expression]): this.type = {
+    transform {
+      case q: QueryPlan[_] => q.transformExpressions(rule).asInstanceOf[PlanType]
+    }.asInstanceOf[this.type]
+  }
+
+  /** Returns all of the expressions present in this query plan operator. */
+  def expressions: Seq[Expression] = {
+    productIterator.flatMap {
+      case e: Expression => e :: Nil
+      case Some(e: Expression) => e :: Nil
+      case seq: Traversable[_] => seq.flatMap {
+        case e: Expression => e :: Nil
+        case other => Nil
+      }
+      case other => Nil
+    }.toSeq
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/joinTypes.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/joinTypes.scala
new file mode 100644
index 0000000000..9f2283ad43
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/joinTypes.scala
@@ -0,0 +1,26 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package plans
+
+sealed abstract class JoinType
+case object Inner extends JoinType
+case object LeftOuter extends JoinType
+case object RightOuter extends JoinType
+case object FullOuter extends JoinType
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/BaseRelation.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/BaseRelation.scala
new file mode 100644
index 0000000000..48ff45c3d3
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/BaseRelation.scala
@@ -0,0 +1,28 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package plans
+package logical
+
+abstract class BaseRelation extends LeafNode {
+  self: Product =>
+
+  def tableName: String
+  def isPartitioned: Boolean = false
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/LogicalPlan.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/LogicalPlan.scala
new file mode 100644
index 0000000000..bc7b6871df
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/LogicalPlan.scala
@@ -0,0 +1,132 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package plans
+package logical
+
+import catalyst.expressions._
+import catalyst.errors._
+import catalyst.types.StructType
+
+abstract class LogicalPlan extends QueryPlan[LogicalPlan] {
+  self: Product =>
+
+  /**
+   * Returns the set of attributes that are referenced by this node
+   * during evaluation.
+   */
+  def references: Set[Attribute]
+
+  /**
+   * Returns the set of attributes that this node takes as
+   * input from its children.
+   */
+  lazy val inputSet: Set[Attribute] = children.flatMap(_.output).toSet
+
+  /**
+   * Returns true if this expression and all its children have been resolved to a specific schema
+   * and false if it is still contains any unresolved placeholders. Implementations of LogicalPlan
+   * can override this (e.g. [[catalyst.analysis.UnresolvedRelation UnresolvedRelation]] should
+   * return `false`).
+   */
+  lazy val resolved: Boolean = !expressions.exists(!_.resolved) && childrenResolved
+
+  /**
+   * Returns true if all its children of this query plan have been resolved.
+   */
+  def childrenResolved = !children.exists(!_.resolved)
+
+  /**
+   * Optionally resolves the given string to a
+   * [[catalyst.expressions.NamedExpression NamedExpression]]. The attribute is expressed as
+   * as string in the following form: `[scope].AttributeName.[nested].[fields]...`.
+   */
+  def resolve(name: String): Option[NamedExpression] = {
+    val parts = name.split("\\.")
+    // Collect all attributes that are output by this nodes children where either the first part
+    // matches the name or where the first part matches the scope and the second part matches the
+    // name.  Return these matches along with any remaining parts, which represent dotted access to
+    // struct fields.
+    val options = children.flatMap(_.output).flatMap { option =>
+      // If the first part of the desired name matches a qualifier for this possible match, drop it.
+      val remainingParts = if (option.qualifiers contains parts.head) parts.drop(1) else parts
+      if (option.name == remainingParts.head) (option, remainingParts.tail.toList) :: Nil else Nil
+    }
+
+    options.distinct match {
+      case (a, Nil) :: Nil => Some(a) // One match, no nested fields, use it.
+      // One match, but we also need to extract the requested nested field.
+      case (a, nestedFields) :: Nil =>
+        a.dataType match {
+          case StructType(fields) =>
+            Some(Alias(nestedFields.foldLeft(a: Expression)(GetField), nestedFields.last)())
+          case _ => None // Don't know how to resolve these field references
+        }
+      case Nil => None         // No matches.
+      case ambiguousReferences =>
+        throw new TreeNodeException(
+          this, s"Ambiguous references to $name: ${ambiguousReferences.mkString(",")}")
+    }
+  }
+}
+
+/**
+ * A logical plan node with no children.
+ */
+abstract class LeafNode extends LogicalPlan with trees.LeafNode[LogicalPlan] {
+  self: Product =>
+
+  // Leaf nodes by definition cannot reference any input attributes.
+  def references = Set.empty
+}
+
+/**
+ * A logical node that represents a non-query command to be executed by the system.  For example,
+ * commands can be used by parsers to represent DDL operations.
+ */
+abstract class Command extends LeafNode {
+  self: Product =>
+  def output = Seq.empty
+}
+
+/**
+ * Returned for commands supported by a given parser, but not catalyst.  In general these are DDL
+ * commands that are passed directly to another system.
+ */
+case class NativeCommand(cmd: String) extends Command
+
+/**
+ * Returned by a parser when the users only wants to see what query plan would be executed, without
+ * actually performing the execution.
+ */
+case class ExplainCommand(plan: LogicalPlan) extends Command
+
+/**
+ * A logical plan node with single child.
+ */
+abstract class UnaryNode extends LogicalPlan with trees.UnaryNode[LogicalPlan] {
+  self: Product =>
+}
+
+/**
+ * A logical plan node with a left and right child.
+ */
+abstract class BinaryNode extends LogicalPlan with trees.BinaryNode[LogicalPlan] {
+  self: Product =>
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/ScriptTransformation.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/ScriptTransformation.scala
new file mode 100644
index 0000000000..1a1a2b9b88
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/ScriptTransformation.scala
@@ -0,0 +1,38 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package plans
+package logical
+
+import expressions._
+
+/**
+ * Transforms the input by forking and running the specified script.
+ *
+ * @param input the set of expression that should be passed to the script.
+ * @param script the command that should be executed.
+ * @param output the attributes that are produced by the script.
+ */
+case class ScriptTransformation(
+    input: Seq[Expression],
+    script: String,
+    output: Seq[Attribute],
+    child: LogicalPlan) extends UnaryNode {
+  def references = input.flatMap(_.references).toSet
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/TestRelation.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/TestRelation.scala
new file mode 100644
index 0000000000..b5905a4456
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/TestRelation.scala
@@ -0,0 +1,47 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package plans
+package logical
+
+import expressions._
+import rules._
+
+object LocalRelation {
+  def apply(output: Attribute*) =
+    new LocalRelation(output)
+}
+
+case class LocalRelation(output: Seq[Attribute], data: Seq[Product] = Nil)
+  extends LeafNode with analysis.MultiInstanceRelation {
+
+  // TODO: Validate schema compliance.
+  def loadData(newData: Seq[Product]) = new LocalRelation(output, data ++ newData)
+
+  /**
+   * Returns an identical copy of this relation with new exprIds for all attributes.  Different
+   * attributes are required when a relation is going to be included multiple times in the same
+   * query.
+   */
+  override final def newInstance: this.type = {
+    LocalRelation(output.map(_.newInstance), data).asInstanceOf[this.type]
+  }
+
+  override protected def stringArgs = Iterator(output)
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/basicOperators.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/basicOperators.scala
new file mode 100644
index 0000000000..8e98aab736
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/basicOperators.scala
@@ -0,0 +1,158 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package plans
+package logical
+
+import expressions._
+
+case class Project(projectList: Seq[NamedExpression], child: LogicalPlan) extends UnaryNode {
+  def output = projectList.map(_.toAttribute)
+  def references = projectList.flatMap(_.references).toSet
+}
+
+/**
+ * Applies a [[catalyst.expressions.Generator Generator]] to a stream of input rows, combining the
+ * output of each into a new stream of rows.  This operation is similar to a `flatMap` in functional
+ * programming with one important additional feature, which allows the input rows to be joined with
+ * their output.
+ * @param join  when true, each output row is implicitly joined with the input tuple that produced
+ *              it.
+ * @param outer when true, each input row will be output at least once, even if the output of the
+ *              given `generator` is empty. `outer` has no effect when `join` is false.
+ * @param alias when set, this string is applied to the schema of the output of the transformation
+ *              as a qualifier.
+ */
+case class Generate(
+    generator: Generator,
+    join: Boolean,
+    outer: Boolean,
+    alias: Option[String],
+    child: LogicalPlan)
+  extends UnaryNode {
+
+  protected def generatorOutput =
+    alias
+      .map(a => generator.output.map(_.withQualifiers(a :: Nil)))
+      .getOrElse(generator.output)
+
+  def output =
+    if (join) child.output ++ generatorOutput else generatorOutput
+
+  def references =
+    if (join) child.outputSet else generator.references
+}
+
+case class Filter(condition: Expression, child: LogicalPlan) extends UnaryNode {
+  def output = child.output
+  def references = condition.references
+}
+
+case class Union(left: LogicalPlan, right: LogicalPlan) extends BinaryNode {
+  // TODO: These aren't really the same attributes as nullability etc might change.
+  def output = left.output
+
+  override lazy val resolved =
+    childrenResolved &&
+    !left.output.zip(right.output).exists { case (l,r) => l.dataType != r.dataType }
+
+  def references = Set.empty
+}
+
+case class Join(
+  left: LogicalPlan,
+  right: LogicalPlan,
+  joinType: JoinType,
+  condition: Option[Expression]) extends BinaryNode {
+
+  def references = condition.map(_.references).getOrElse(Set.empty)
+  def output = left.output ++ right.output
+}
+
+case class InsertIntoTable(
+    table: BaseRelation,
+    partition: Map[String, Option[String]],
+    child: LogicalPlan,
+    overwrite: Boolean)
+  extends LogicalPlan {
+  // The table being inserted into is a child for the purposes of transformations.
+  def children = table :: child :: Nil
+  def references = Set.empty
+  def output = child.output
+
+  override lazy val resolved = childrenResolved && child.output.zip(table.output).forall {
+    case (childAttr, tableAttr) => childAttr.dataType == tableAttr.dataType
+  }
+}
+
+case class InsertIntoCreatedTable(
+    databaseName: Option[String],
+    tableName: String,
+    child: LogicalPlan) extends UnaryNode {
+  def references = Set.empty
+  def output = child.output
+}
+
+case class WriteToFile(
+    path: String,
+    child: LogicalPlan) extends UnaryNode {
+  def references = Set.empty
+  def output = child.output
+}
+
+case class Sort(order: Seq[SortOrder], child: LogicalPlan) extends UnaryNode {
+  def output = child.output
+  def references = order.flatMap(_.references).toSet
+}
+
+case class Aggregate(
+    groupingExpressions: Seq[Expression],
+    aggregateExpressions: Seq[NamedExpression],
+    child: LogicalPlan)
+  extends UnaryNode {
+
+  def output = aggregateExpressions.map(_.toAttribute)
+  def references = child.references
+}
+
+case class StopAfter(limit: Expression, child: LogicalPlan) extends UnaryNode {
+  def output = child.output
+  def references = limit.references
+}
+
+case class Subquery(alias: String, child: LogicalPlan) extends UnaryNode {
+  def output = child.output.map(_.withQualifiers(alias :: Nil))
+  def references = Set.empty
+}
+
+case class Sample(fraction: Double, withReplacement: Boolean, seed: Int, child: LogicalPlan)
+    extends UnaryNode {
+
+  def output = child.output
+  def references = Set.empty
+}
+
+case class Distinct(child: LogicalPlan) extends UnaryNode {
+  def output = child.output
+  def references = child.outputSet
+}
+
+case object NoRelation extends LeafNode {
+  def output = Nil
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/partitioning.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/partitioning.scala
new file mode 100644
index 0000000000..f7fcdc5fdb
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/partitioning.scala
@@ -0,0 +1,46 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package plans
+package logical
+
+import expressions._
+
+/**
+ * Performs a physical redistribution of the data.  Used when the consumer of the query
+ * result have expectations about the distribution and ordering of partitioned input data.
+ */
+abstract class RedistributeData extends UnaryNode {
+  self: Product =>
+
+  def output = child.output
+}
+
+case class SortPartitions(sortExpressions: Seq[SortOrder], child: LogicalPlan)
+    extends RedistributeData {
+
+  def references = sortExpressions.flatMap(_.references).toSet
+}
+
+case class Repartition(partitionExpressions: Seq[Expression], child: LogicalPlan)
+    extends RedistributeData {
+
+  def references = partitionExpressions.flatMap(_.references).toSet
+}
+
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/package.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/package.scala
new file mode 100644
index 0000000000..a40ab4bbb1
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/package.scala
@@ -0,0 +1,25 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+
+/**
+ * A a collection of common abstractions for query plans as well as
+ * a base logical plan representation.
+ */
+package object plans
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/physical/partitioning.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/physical/partitioning.scala
new file mode 100644
index 0000000000..2d8f3ad335
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/physical/partitioning.scala
@@ -0,0 +1,201 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package plans
+package physical
+
+import expressions._
+import types._
+
+/**
+ * Specifies how tuples that share common expressions will be distributed when a query is executed
+ * in parallel on many machines.  Distribution can be used to refer to two distinct physical
+ * properties:
+ *  - Inter-node partitioning of data: In this case the distribution describes how tuples are
+ *    partitioned across physical machines in a cluster.  Knowing this property allows some
+ *    operators (e.g., Aggregate) to perform partition local operations instead of global ones.
+ *  - Intra-partition ordering of data: In this case the distribution describes guarantees made
+ *    about how tuples are distributed within a single partition.
+ */
+sealed trait Distribution
+
+/**
+ * Represents a distribution where no promises are made about co-location of data.
+ */
+case object UnspecifiedDistribution extends Distribution
+
+/**
+ * Represents a distribution that only has a single partition and all tuples of the dataset
+ * are co-located.
+ */
+case object AllTuples extends Distribution
+
+/**
+ * Represents data where tuples that share the same values for the `clustering`
+ * [[catalyst.expressions.Expression Expressions]] will be co-located. Based on the context, this
+ * can mean such tuples are either co-located in the same partition or they will be contiguous
+ * within a single partition.
+ */
+case class ClusteredDistribution(clustering: Seq[Expression]) extends Distribution {
+  require(
+    clustering != Nil,
+    "The clustering expressions of a ClusteredDistribution should not be Nil. " +
+      "An AllTuples should be used to represent a distribution that only has " +
+      "a single partition.")
+}
+
+/**
+ * Represents data where tuples have been ordered according to the `ordering`
+ * [[catalyst.expressions.Expression Expressions]].  This is a strictly stronger guarantee than
+ * [[ClusteredDistribution]] as an ordering will ensure that tuples that share the same value for
+ * the ordering expressions are contiguous and will never be split across partitions.
+ */
+case class OrderedDistribution(ordering: Seq[SortOrder]) extends Distribution {
+  require(
+    ordering != Nil,
+    "The ordering expressions of a OrderedDistribution should not be Nil. " +
+      "An AllTuples should be used to represent a distribution that only has " +
+      "a single partition.")
+
+  def clustering = ordering.map(_.child).toSet
+}
+
+sealed trait Partitioning {
+  /** Returns the number of partitions that the data is split across */
+  val numPartitions: Int
+
+  /**
+   * Returns true iff the guarantees made by this
+   * [[catalyst.plans.physical.Partitioning Partitioning]] are sufficient to satisfy
+   * the partitioning scheme mandated by the `required`
+   * [[catalyst.plans.physical.Distribution Distribution]], i.e. the current dataset does not
+   * need to be re-partitioned for the `required` Distribution (it is possible that tuples within
+   * a partition need to be reorganized).
+   */
+  def satisfies(required: Distribution): Boolean
+
+  /**
+   * Returns true iff all distribution guarantees made by this partitioning can also be made
+   * for the `other` specified partitioning.
+   * For example, two [[catalyst.plans.physical.HashPartitioning HashPartitioning]]s are
+   * only compatible if the `numPartitions` of them is the same.
+   */
+  def compatibleWith(other: Partitioning): Boolean
+}
+
+case class UnknownPartitioning(numPartitions: Int) extends Partitioning {
+  override def satisfies(required: Distribution): Boolean = required match {
+    case UnspecifiedDistribution => true
+    case _ => false
+  }
+
+  override def compatibleWith(other: Partitioning): Boolean = other match {
+    case UnknownPartitioning(_) => true
+    case _ => false
+  }
+}
+
+case object SinglePartition extends Partitioning {
+  val numPartitions = 1
+
+  override def satisfies(required: Distribution): Boolean = true
+
+  override def compatibleWith(other: Partitioning) = other match {
+    case SinglePartition => true
+    case _ => false
+  }
+}
+
+case object BroadcastPartitioning extends Partitioning {
+  val numPartitions = 1
+
+  override def satisfies(required: Distribution): Boolean = true
+
+  override def compatibleWith(other: Partitioning) = other match {
+    case SinglePartition => true
+    case _ => false
+  }
+}
+
+/**
+ * Represents a partitioning where rows are split up across partitions based on the hash
+ * of `expressions`.  All rows where `expressions` evaluate to the same values are guaranteed to be
+ * in the same partition.
+ */
+case class HashPartitioning(expressions: Seq[Expression], numPartitions: Int)
+  extends Expression
+  with Partitioning {
+
+  def children = expressions
+  def references = expressions.flatMap(_.references).toSet
+  def nullable = false
+  def dataType = IntegerType
+
+  lazy val clusteringSet = expressions.toSet
+
+  override def satisfies(required: Distribution): Boolean = required match {
+    case UnspecifiedDistribution => true
+    case ClusteredDistribution(requiredClustering) =>
+      clusteringSet.subsetOf(requiredClustering.toSet)
+    case _ => false
+  }
+
+  override def compatibleWith(other: Partitioning) = other match {
+    case BroadcastPartitioning => true
+    case h: HashPartitioning if h == this => true
+    case _ => false
+  }
+}
+
+/**
+ * Represents a partitioning where rows are split across partitions based on some total ordering of
+ * the expressions specified in `ordering`.  When data is partitioned in this manner the following
+ * two conditions are guaranteed to hold:
+ *  - All row where the expressions in `ordering` evaluate to the same values will be in the same
+ *    partition.
+ *  - Each partition will have a `min` and `max` row, relative to the given ordering.  All rows
+ *    that are in between `min` and `max` in this `ordering` will reside in this partition.
+ */
+case class RangePartitioning(ordering: Seq[SortOrder], numPartitions: Int)
+  extends Expression
+  with Partitioning {
+
+  def children = ordering
+  def references = ordering.flatMap(_.references).toSet
+  def nullable = false
+  def dataType = IntegerType
+
+  lazy val clusteringSet = ordering.map(_.child).toSet
+
+  override def satisfies(required: Distribution): Boolean = required match {
+    case UnspecifiedDistribution => true
+    case OrderedDistribution(requiredOrdering) =>
+      val minSize = Seq(requiredOrdering.size, ordering.size).min
+      requiredOrdering.take(minSize) == ordering.take(minSize)
+    case ClusteredDistribution(requiredClustering) =>
+      clusteringSet.subsetOf(requiredClustering.toSet)
+    case _ => false
+  }
+
+  override def compatibleWith(other: Partitioning) = other match {
+    case BroadcastPartitioning => true
+    case r: RangePartitioning if r == this => true
+    case _ => false
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/rules/Rule.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/rules/Rule.scala
new file mode 100644
index 0000000000..6ff4891a3f
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/rules/Rule.scala
@@ -0,0 +1,33 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package rules
+
+import trees._
+
+abstract class Rule[TreeType <: TreeNode[_]] extends Logging {
+
+  /** Name for this rule, automatically inferred based on class name. */
+  val ruleName: String = {
+    val className = getClass.getName
+    if (className endsWith "$") className.dropRight(1) else className
+  }
+
+  def apply(plan: TreeType): TreeType
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/rules/RuleExecutor.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/rules/RuleExecutor.scala
new file mode 100644
index 0000000000..68ae30cde1
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/rules/RuleExecutor.scala
@@ -0,0 +1,79 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package rules
+
+import trees._
+import util._
+
+abstract class RuleExecutor[TreeType <: TreeNode[_]] extends Logging {
+
+  /**
+   * An execution strategy for rules that indicates the maximum number of executions. If the
+   * execution reaches fix point (i.e. converge) before maxIterations, it will stop.
+   */
+  abstract class Strategy { def maxIterations: Int }
+
+  /** A strategy that only runs once. */
+  case object Once extends Strategy { val maxIterations = 1 }
+
+  /** A strategy that runs until fix point or maxIterations times, whichever comes first. */
+  case class FixedPoint(maxIterations: Int) extends Strategy
+
+  /** A batch of rules. */
+  protected case class Batch(name: String, strategy: Strategy, rules: Rule[TreeType]*)
+
+  /** Defines a sequence of rule batches, to be overridden by the implementation. */
+  protected val batches: Seq[Batch]
+
+  /**
+   * Executes the batches of rules defined by the subclass. The batches are executed serially
+   * using the defined execution strategy. Within each batch, rules are also executed serially.
+   */
+  def apply(plan: TreeType): TreeType = {
+    var curPlan = plan
+
+    batches.foreach { batch =>
+      var iteration = 1
+      var lastPlan = curPlan
+      curPlan = batch.rules.foldLeft(curPlan) { case (curPlan, rule) => rule(curPlan) }
+
+      // Run until fix point (or the max number of iterations as specified in the strategy.
+      while (iteration < batch.strategy.maxIterations && !curPlan.fastEquals(lastPlan)) {
+        lastPlan = curPlan
+        curPlan = batch.rules.foldLeft(curPlan) {
+          case (curPlan, rule) =>
+            val result = rule(curPlan)
+            if (!result.fastEquals(curPlan)) {
+              logger.debug(
+                s"""
+                  |=== Applying Rule ${rule.ruleName} ===
+                  |${sideBySide(curPlan.treeString, result.treeString).mkString("\n")}
+                """.stripMargin)
+            }
+
+            result
+        }
+        iteration += 1
+      }
+    }
+
+    curPlan
+  }
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/rules/package.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/rules/package.scala
new file mode 100644
index 0000000000..26ab543082
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/rules/package.scala
@@ -0,0 +1,24 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+
+/**
+ * A framework for applying batches rewrite rules to trees, possibly to fixed point.
+ */
+package object rules
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/trees/TreeNode.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/trees/TreeNode.scala
new file mode 100644
index 0000000000..76ede87e4e
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/trees/TreeNode.scala
@@ -0,0 +1,364 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package trees
+
+import errors._
+
+object TreeNode {
+  private val currentId = new java.util.concurrent.atomic.AtomicLong
+  protected def nextId() = currentId.getAndIncrement()
+}
+
+/** Used by [[TreeNode.getNodeNumbered]] when traversing the tree for a given number */
+private class MutableInt(var i: Int)
+
+abstract class TreeNode[BaseType <: TreeNode[BaseType]] {
+  self: BaseType with Product =>
+
+  /** Returns a Seq of the children of this node */
+  def children: Seq[BaseType]
+
+  /**
+   * A globally unique id for this specific instance. Not preserved across copies.
+   * Unlike `equals`, `id` can be used to differentiate distinct but structurally
+   * identical branches of a tree.
+   */
+  val id = TreeNode.nextId()
+
+  /**
+   * Returns true if other is the same [[catalyst.trees.TreeNode TreeNode]] instance.  Unlike
+   * `equals` this function will return false for different instances of structurally identical
+   * trees.
+   */
+  def sameInstance(other: TreeNode[_]): Boolean = {
+    this.id == other.id
+  }
+
+  /**
+   * Faster version of equality which short-circuits when two treeNodes are the same instance.
+   * We don't just override Object.Equals, as doing so prevents the scala compiler from from
+   * generating case class `equals` methods
+   */
+  def fastEquals(other: TreeNode[_]): Boolean = {
+    sameInstance(other) || this == other
+  }
+
+  /**
+   * Runs the given function on this node and then recursively on [[children]].
+   * @param f the function to be applied to each node in the tree.
+   */
+  def foreach(f: BaseType => Unit): Unit = {
+    f(this)
+    children.foreach(_.foreach(f))
+  }
+
+  /**
+   * Returns a Seq containing the result of applying the given function to each
+   * node in this tree in a preorder traversal.
+   * @param f the function to be applied.
+   */
+  def map[A](f: BaseType => A): Seq[A] = {
+    val ret = new collection.mutable.ArrayBuffer[A]()
+    foreach(ret += f(_))
+    ret
+  }
+
+  /**
+   * Returns a Seq by applying a function to all nodes in this tree and using the elements of the
+   * resulting collections.
+   */
+  def flatMap[A](f: BaseType => TraversableOnce[A]): Seq[A] = {
+    val ret = new collection.mutable.ArrayBuffer[A]()
+    foreach(ret ++= f(_))
+    ret
+  }
+
+  /**
+   * Returns a Seq containing the result of applying a partial function to all elements in this
+   * tree on which the function is defined.
+   */
+  def collect[B](pf: PartialFunction[BaseType, B]): Seq[B] = {
+    val ret = new collection.mutable.ArrayBuffer[B]()
+    val lifted = pf.lift
+    foreach(node => lifted(node).foreach(ret.+=))
+    ret
+  }
+
+  /**
+   * Returns a copy of this node where `f` has been applied to all the nodes children.
+   */
+  def mapChildren(f: BaseType => BaseType): this.type = {
+    var changed = false
+    val newArgs = productIterator.map {
+      case arg: TreeNode[_] if children contains arg =>
+        val newChild = f(arg.asInstanceOf[BaseType])
+        if (newChild fastEquals arg) {
+          arg
+        } else {
+          changed = true
+          newChild
+        }
+      case nonChild: AnyRef => nonChild
+      case null => null
+    }.toArray
+    if (changed) makeCopy(newArgs) else this
+  }
+
+  /**
+   * Returns a copy of this node with the children replaced.
+   * TODO: Validate somewhere (in debug mode?) that children are ordered correctly.
+   */
+  def withNewChildren(newChildren: Seq[BaseType]): this.type = {
+    assert(newChildren.size == children.size, "Incorrect number of children")
+    var changed = false
+    val remainingNewChildren = newChildren.toBuffer
+    val remainingOldChildren = children.toBuffer
+    val newArgs = productIterator.map {
+      case arg: TreeNode[_] if children contains arg =>
+        val newChild = remainingNewChildren.remove(0)
+        val oldChild = remainingOldChildren.remove(0)
+        if (newChild fastEquals oldChild) {
+          oldChild
+        } else {
+          changed = true
+          newChild
+        }
+      case nonChild: AnyRef => nonChild
+      case null => null
+    }.toArray
+
+    if (changed) makeCopy(newArgs) else this
+  }
+
+  /**
+   * Returns a copy of this node where `rule` has been recursively applied to the tree.
+   * When `rule` does not apply to a given node it is left unchanged.
+   * Users should not expect a specific directionality. If a specific directionality is needed,
+   * transformDown or transformUp should be used.
+   * @param rule the function use to transform this nodes children
+   */
+  def transform(rule: PartialFunction[BaseType, BaseType]): BaseType = {
+    transformDown(rule)
+  }
+
+  /**
+   * Returns a copy of this node where `rule` has been recursively applied to it and all of its
+   * children (pre-order). When `rule` does not apply to a given node it is left unchanged.
+   * @param rule the function used to transform this nodes children
+   */
+  def transformDown(rule: PartialFunction[BaseType, BaseType]): BaseType = {
+    val afterRule = rule.applyOrElse(this, identity[BaseType])
+    // Check if unchanged and then possibly return old copy to avoid gc churn.
+    if (this fastEquals afterRule) {
+      transformChildrenDown(rule)
+    } else {
+      afterRule.transformChildrenDown(rule)
+    }
+  }
+
+  /**
+   * Returns a copy of this node where `rule` has been recursively applied to all the children of
+   * this node.  When `rule` does not apply to a given node it is left unchanged.
+   * @param rule the function used to transform this nodes children
+   */
+  def transformChildrenDown(rule: PartialFunction[BaseType, BaseType]): this.type = {
+    var changed = false
+    val newArgs = productIterator.map {
+      case arg: TreeNode[_] if children contains arg =>
+        val newChild = arg.asInstanceOf[BaseType].transformDown(rule)
+        if (!(newChild fastEquals arg)) {
+          changed = true
+          newChild
+        } else {
+          arg
+        }
+      case m: Map[_,_] => m
+      case args: Traversable[_] => args.map {
+        case arg: TreeNode[_] if children contains arg =>
+          val newChild = arg.asInstanceOf[BaseType].transformDown(rule)
+          if (!(newChild fastEquals arg)) {
+            changed = true
+            newChild
+          } else {
+            arg
+          }
+        case other => other
+      }
+      case nonChild: AnyRef => nonChild
+      case null => null
+    }.toArray
+    if (changed) makeCopy(newArgs) else this
+  }
+
+  /**
+   * Returns a copy of this node where `rule` has been recursively applied first to all of its
+   * children and then itself (post-order). When `rule` does not apply to a given node, it is left
+   * unchanged.
+   * @param rule the function use to transform this nodes children
+   */
+  def transformUp(rule: PartialFunction[BaseType, BaseType]): BaseType = {
+    val afterRuleOnChildren = transformChildrenUp(rule);
+    if (this fastEquals afterRuleOnChildren) {
+      rule.applyOrElse(this, identity[BaseType])
+    } else {
+      rule.applyOrElse(afterRuleOnChildren, identity[BaseType])
+    }
+  }
+
+  def transformChildrenUp(rule: PartialFunction[BaseType, BaseType]): this.type = {
+    var changed = false
+    val newArgs = productIterator.map {
+      case arg: TreeNode[_] if children contains arg =>
+        val newChild = arg.asInstanceOf[BaseType].transformUp(rule)
+        if (!(newChild fastEquals arg)) {
+          changed = true
+          newChild
+        } else {
+          arg
+        }
+      case m: Map[_,_] => m
+      case args: Traversable[_] => args.map {
+        case arg: TreeNode[_] if children contains arg =>
+          val newChild = arg.asInstanceOf[BaseType].transformUp(rule)
+          if (!(newChild fastEquals arg)) {
+            changed = true
+            newChild
+          } else {
+            arg
+          }
+        case other => other
+      }
+      case nonChild: AnyRef => nonChild
+      case null => null
+    }.toArray
+    if (changed) makeCopy(newArgs) else this
+  }
+
+  /**
+   * Args to the constructor that should be copied, but not transformed.
+   * These are appended to the transformed args automatically by makeCopy
+   * @return
+   */
+  protected def otherCopyArgs: Seq[AnyRef] = Nil
+
+  /**
+   * Creates a copy of this type of tree node after a transformation.
+   * Must be overridden by child classes that have constructor arguments
+   * that are not present in the productIterator.
+   * @param newArgs the new product arguments.
+   */
+  def makeCopy(newArgs: Array[AnyRef]): this.type = attachTree(this, "makeCopy") {
+    try {
+      val defaultCtor = getClass.getConstructors.head
+      if (otherCopyArgs.isEmpty) {
+        defaultCtor.newInstance(newArgs: _*).asInstanceOf[this.type]
+      } else {
+        defaultCtor.newInstance((newArgs ++ otherCopyArgs).toArray: _*).asInstanceOf[this.type]
+      }
+    } catch {
+      case e: java.lang.IllegalArgumentException =>
+        throw new TreeNodeException(
+          this, s"Failed to copy node.  Is otherCopyArgs specified correctly for $nodeName?")
+    }
+  }
+
+  /** Returns the name of this type of TreeNode.  Defaults to the class name. */
+  def nodeName = getClass.getSimpleName
+
+  /**
+   * The arguments that should be included in the arg string.  Defaults to the `productIterator`.
+   */
+  protected def stringArgs = productIterator
+
+  /** Returns a string representing the arguments to this node, minus any children */
+  def argString: String = productIterator.flatMap {
+    case tn: TreeNode[_] if children contains tn => Nil
+    case tn: TreeNode[_] if tn.toString contains "\n" => s"(${tn.simpleString})" :: Nil
+    case seq: Seq[_] => seq.mkString("[", ",", "]") :: Nil
+    case set: Set[_] => set.mkString("{", ",", "}") :: Nil
+    case other => other :: Nil
+  }.mkString(", ")
+
+  /** String representation of this node without any children */
+  def simpleString = s"$nodeName $argString"
+
+  override def toString: String = treeString
+
+  /** Returns a string representation of the nodes in this tree */
+  def treeString = generateTreeString(0, new StringBuilder).toString
+
+  /**
+   * Returns a string representation of the nodes in this tree, where each operator is numbered.
+   * The numbers can be used with [[trees.TreeNode.apply apply]] to easily access specific subtrees.
+   */
+  def numberedTreeString =
+    treeString.split("\n").zipWithIndex.map { case (line, i) => f"$i%02d $line" }.mkString("\n")
+
+  /**
+   * Returns the tree node at the specified number.
+   * Numbers for each node can be found in the [[numberedTreeString]].
+   */
+  def apply(number: Int): BaseType = getNodeNumbered(new MutableInt(number))
+
+  protected def getNodeNumbered(number: MutableInt): BaseType = {
+    if (number.i < 0) {
+      null.asInstanceOf[BaseType]
+    } else if (number.i == 0) {
+      this
+    } else {
+      number.i -= 1
+      children.map(_.getNodeNumbered(number)).find(_ != null).getOrElse(null.asInstanceOf[BaseType])
+    }
+  }
+
+  /** Appends the string represent of this node and its children to the given StringBuilder. */
+  protected def generateTreeString(depth: Int, builder: StringBuilder): StringBuilder = {
+    builder.append(" " * depth)
+    builder.append(simpleString)
+    builder.append("\n")
+    children.foreach(_.generateTreeString(depth + 1, builder))
+    builder
+  }
+}
+
+/**
+ * A [[TreeNode]] that has two children, [[left]] and [[right]].
+ */
+trait BinaryNode[BaseType <: TreeNode[BaseType]] {
+  def left: BaseType
+  def right: BaseType
+
+  def children = Seq(left, right)
+}
+
+/**
+ * A [[TreeNode]] with no children.
+ */
+trait LeafNode[BaseType <: TreeNode[BaseType]] {
+  def children = Nil
+}
+
+/**
+ * A [[TreeNode]] with a single [[child]].
+ */
+trait UnaryNode[BaseType <: TreeNode[BaseType]] {
+  def child: BaseType
+  def children = child :: Nil
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/trees/package.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/trees/package.scala
new file mode 100644
index 0000000000..e2da1d2439
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/trees/package.scala
@@ -0,0 +1,38 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+
+/**
+ * A library for easily manipulating trees of operators.  Operators that extend TreeNode are
+ * granted the following interface:
+ * <ul>
+ *   <li>Scala collection like methods (foreach, map, flatMap, collect, etc)</li>
+ *   <li>
+ *     transform - accepts a partial function that is used to generate a new tree.  When the
+ *     partial function can be applied to a given tree segment, that segment is replaced with the
+ *     result.  After attempting to apply the partial function to a given node, the transform
+ *     function recursively attempts to apply the function to that node's children.
+ *   </li>
+ *   <li>debugging support - pretty printing, easy splicing of trees, etc.</li>
+ * </ul>
+ */
+package object trees {
+  // Since we want tree nodes to be lightweight, we create one logger for all treenode instances.
+  protected val logger = Logger("catalyst.trees")
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/types/dataTypes.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/types/dataTypes.scala
new file mode 100644
index 0000000000..6eb2b62ecc
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/types/dataTypes.scala
@@ -0,0 +1,137 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package types
+
+import expressions.Expression
+
+abstract class DataType {
+  /** Matches any expression that evaluates to this DataType */
+  def unapply(a: Expression): Boolean = a match {
+    case e: Expression if e.dataType == this => true
+    case _ => false
+  }
+}
+
+case object NullType extends DataType
+
+abstract class NativeType extends DataType {
+  type JvmType
+  val ordering: Ordering[JvmType]
+}
+
+case object StringType extends NativeType {
+  type JvmType = String
+  val ordering = implicitly[Ordering[JvmType]]
+}
+case object BinaryType extends DataType {
+  type JvmType = Array[Byte]
+}
+case object BooleanType extends NativeType {
+  type JvmType = Boolean
+  val ordering = implicitly[Ordering[JvmType]]
+}
+
+abstract class NumericType extends NativeType {
+  // Unfortunately we can't get this implicitly as that breaks Spark Serialization. In order for
+  // implicitly[Numeric[JvmType]] to be valid, we have to change JvmType from a type variable to a
+  // type parameter and and add a numeric annotation (i.e., [JvmType : Numeric]). This gets
+  // desugared by the compiler into an argument to the objects constructor. This means there is no
+  // longer an no argument constructor and thus the JVM cannot serialize the object anymore.
+  val numeric: Numeric[JvmType]
+}
+
+/** Matcher for any expressions that evaluate to [[IntegralType]]s */
+object IntegralType {
+  def unapply(a: Expression): Boolean = a match {
+    case e: Expression if e.dataType.isInstanceOf[IntegralType] => true
+    case _ => false
+  }
+}
+
+abstract class IntegralType extends NumericType {
+  val integral: Integral[JvmType]
+}
+
+case object LongType extends IntegralType {
+  type JvmType = Long
+  val numeric = implicitly[Numeric[Long]]
+  val integral = implicitly[Integral[Long]]
+  val ordering = implicitly[Ordering[JvmType]]
+}
+
+case object IntegerType extends IntegralType {
+  type JvmType = Int
+  val numeric = implicitly[Numeric[Int]]
+  val integral = implicitly[Integral[Int]]
+  val ordering = implicitly[Ordering[JvmType]]
+}
+
+case object ShortType extends IntegralType {
+  type JvmType = Short
+  val numeric = implicitly[Numeric[Short]]
+  val integral = implicitly[Integral[Short]]
+  val ordering = implicitly[Ordering[JvmType]]
+}
+
+case object ByteType extends IntegralType {
+  type JvmType = Byte
+  val numeric = implicitly[Numeric[Byte]]
+  val integral = implicitly[Integral[Byte]]
+  val ordering = implicitly[Ordering[JvmType]]
+}
+
+/** Matcher for any expressions that evaluate to [[FractionalType]]s */
+object FractionalType {
+  def unapply(a: Expression): Boolean = a match {
+    case e: Expression if e.dataType.isInstanceOf[FractionalType] => true
+    case _ => false
+  }
+}
+abstract class FractionalType extends NumericType {
+  val fractional: Fractional[JvmType]
+}
+
+case object DecimalType extends FractionalType {
+  type JvmType = BigDecimal
+  val numeric = implicitly[Numeric[BigDecimal]]
+  val fractional = implicitly[Fractional[BigDecimal]]
+  val ordering = implicitly[Ordering[JvmType]]
+}
+
+case object DoubleType extends FractionalType {
+  type JvmType = Double
+  val numeric = implicitly[Numeric[Double]]
+  val fractional = implicitly[Fractional[Double]]
+  val ordering = implicitly[Ordering[JvmType]]
+}
+
+case object FloatType extends FractionalType {
+  type JvmType = Float
+  val numeric = implicitly[Numeric[Float]]
+  val fractional = implicitly[Fractional[Float]]
+  val ordering = implicitly[Ordering[JvmType]]
+}
+
+case class ArrayType(elementType: DataType) extends DataType
+
+case class StructField(name: String, dataType: DataType, nullable: Boolean)
+case class StructType(fields: Seq[StructField]) extends DataType
+
+case class MapType(keyType: DataType, valueType: DataType) extends DataType
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/types/package.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/types/package.scala
new file mode 100644
index 0000000000..b65a5617d9
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/types/package.scala
@@ -0,0 +1,24 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+/**
+ * Contains a type system for attributes produced by relations, including complex types like
+ * structs, arrays and maps.
+ */
+package object types
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/package.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/package.scala
new file mode 100644
index 0000000000..52adea2661
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/package.scala
@@ -0,0 +1,122 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+
+import java.io.{PrintWriter, ByteArrayOutputStream, FileInputStream, File}
+
+package object util {
+  /**
+   * Returns a path to a temporary file that probably does not exist.
+   * Note, there is always the race condition that someone created this
+   * file since the last time we checked.  Thus, this shouldn't be used
+   * for anything security conscious.
+   */
+  def getTempFilePath(prefix: String, suffix: String = ""): File = {
+    val tempFile = File.createTempFile(prefix, suffix)
+    tempFile.delete()
+    tempFile
+  }
+
+  def fileToString(file: File, encoding: String = "UTF-8") = {
+    val inStream = new FileInputStream(file)
+    val outStream = new ByteArrayOutputStream
+    try {
+      var reading = true
+      while ( reading ) {
+        inStream.read() match {
+          case -1 => reading = false
+          case c => outStream.write(c)
+        }
+      }
+      outStream.flush()
+    }
+    finally {
+      inStream.close()
+    }
+    new String(outStream.toByteArray, encoding)
+  }
+
+  def resourceToString(
+      resource:String,
+      encoding: String = "UTF-8",
+      classLoader: ClassLoader = this.getClass.getClassLoader) = {
+    val inStream = classLoader.getResourceAsStream(resource)
+    val outStream = new ByteArrayOutputStream
+    try {
+      var reading = true
+      while ( reading ) {
+        inStream.read() match {
+          case -1 => reading = false
+          case c => outStream.write(c)
+        }
+      }
+      outStream.flush()
+    }
+    finally {
+      inStream.close()
+    }
+    new String(outStream.toByteArray, encoding)
+  }
+
+  def stringToFile(file: File, str: String): File = {
+    val out = new PrintWriter(file)
+    out.write(str)
+    out.close()
+    file
+  }
+
+  def sideBySide(left: String, right: String): Seq[String] = {
+    sideBySide(left.split("\n"), right.split("\n"))
+  }
+
+  def sideBySide(left: Seq[String], right: Seq[String]): Seq[String] = {
+    val maxLeftSize = left.map(_.size).max
+    val leftPadded = left ++ Seq.fill(math.max(right.size - left.size, 0))("")
+    val rightPadded = right ++ Seq.fill(math.max(left.size - right.size, 0))("")
+
+    leftPadded.zip(rightPadded).map {
+      case (l, r) => (if (l == r) " " else "!") + l + (" " * ((maxLeftSize - l.size) + 3)) + r
+    }
+  }
+
+  def stackTraceToString(t: Throwable): String = {
+    val out = new java.io.ByteArrayOutputStream
+    val writer = new PrintWriter(out)
+    t.printStackTrace(writer)
+    writer.flush()
+    new String(out.toByteArray)
+  }
+
+  def stringOrNull(a: AnyRef) = if (a == null) null else a.toString
+
+  def benchmark[A](f: => A): A = {
+    val startTime = System.nanoTime()
+    val ret = f
+    val endTime = System.nanoTime()
+    println(s"${(endTime - startTime).toDouble / 1000000}ms")
+    ret
+  }
+
+  /* FIX ME
+  implicit class debugLogging(a: AnyRef) {
+    def debugLogging() {
+      org.apache.log4j.Logger.getLogger(a.getClass.getName).setLevel(org.apache.log4j.Level.DEBUG)
+    }
+  } */
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/package.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/package.scala
new file mode 100644
index 0000000000..9ec31689b5
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/package.scala
@@ -0,0 +1,49 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark
+
+/**
+ * Allows the execution of relational queries, including those expressed in SQL using Spark.
+ *
+ * Note that this package is located in catalyst instead of in core so that all subprojects can
+ * inherit the settings from this package object.
+ */
+package object sql {
+
+  protected[sql] def Logger(name: String) =
+    com.typesafe.scalalogging.slf4j.Logger(org.slf4j.LoggerFactory.getLogger(name))
+
+  protected[sql] type Logging = com.typesafe.scalalogging.slf4j.Logging
+
+  type Row = catalyst.expressions.Row
+
+  object Row {
+    /**
+     * This method can be used to extract fields from a [[Row]] object in a pattern match. Example:
+     * {{{
+     * import org.apache.spark.sql._
+     *
+     * val pairs = sql("SELECT key, value FROM src").rdd.map {
+     *   case Row(key: Int, value: String) =>
+     *     key -> value
+     * }
+     * }}}
+     */
+    def unapplySeq(row: Row): Some[Seq[Any]] = Some(row)
+  }
+}
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/AnalysisSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/AnalysisSuite.scala
new file mode 100644
index 0000000000..1fd0d26b6f
--- /dev/null
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/AnalysisSuite.scala
@@ -0,0 +1,41 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package analysis
+
+import org.scalatest.FunSuite
+
+import analysis._
+import expressions._
+import plans.logical._
+import types._
+
+import dsl._
+import dsl.expressions._
+
+class AnalysisSuite extends FunSuite {
+  val analyze = SimpleAnalyzer
+
+  val testRelation = LocalRelation('a.int)
+
+  test("analyze project") {
+    assert(analyze(Project(Seq(UnresolvedAttribute("a")), testRelation)) === Project(testRelation.output, testRelation))
+
+  }
+}
\ No newline at end of file
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/DistributionSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/DistributionSuite.scala
new file mode 100644
index 0000000000..fb25e1c246
--- /dev/null
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/DistributionSuite.scala
@@ -0,0 +1,175 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+
+import org.scalatest.FunSuite
+
+import org.apache.spark.sql.catalyst.plans.physical._
+
+/* Implicit conversions */
+import org.apache.spark.sql.catalyst.dsl.expressions._
+
+class DistributionSuite extends FunSuite {
+
+  protected def checkSatisfied(
+      inputPartitioning: Partitioning,
+      requiredDistribution: Distribution,
+      satisfied: Boolean) {
+    if (inputPartitioning.satisfies(requiredDistribution) != satisfied)
+      fail(
+        s"""
+        |== Input Partitioning ==
+        |$inputPartitioning
+        |== Required Distribution ==
+        |$requiredDistribution
+        |== Does input partitioning satisfy required distribution? ==
+        |Expected $satisfied got ${inputPartitioning.satisfies(requiredDistribution)}
+        """.stripMargin)
+  }
+
+  test("HashPartitioning is the output partitioning") {
+    // Cases which do not need an exchange between two data properties.
+    checkSatisfied(
+      HashPartitioning(Seq('a, 'b, 'c), 10),
+      UnspecifiedDistribution,
+      true)
+
+    checkSatisfied(
+      HashPartitioning(Seq('a, 'b, 'c), 10),
+      ClusteredDistribution(Seq('a, 'b, 'c)),
+      true)
+
+    checkSatisfied(
+      HashPartitioning(Seq('b, 'c), 10),
+      ClusteredDistribution(Seq('a, 'b, 'c)),
+      true)
+
+    checkSatisfied(
+      SinglePartition,
+      ClusteredDistribution(Seq('a, 'b, 'c)),
+      true)
+
+    checkSatisfied(
+      SinglePartition,
+      OrderedDistribution(Seq('a.asc, 'b.asc, 'c.asc)),
+      true)
+
+    // Cases which need an exchange between two data properties.
+    checkSatisfied(
+      HashPartitioning(Seq('a, 'b, 'c), 10),
+      ClusteredDistribution(Seq('b, 'c)),
+      false)
+
+    checkSatisfied(
+      HashPartitioning(Seq('a, 'b, 'c), 10),
+      ClusteredDistribution(Seq('d, 'e)),
+      false)
+
+    checkSatisfied(
+      HashPartitioning(Seq('a, 'b, 'c), 10),
+      AllTuples,
+      false)
+
+    checkSatisfied(
+      HashPartitioning(Seq('a, 'b, 'c), 10),
+      OrderedDistribution(Seq('a.asc, 'b.asc, 'c.asc)),
+      false)
+
+    checkSatisfied(
+      HashPartitioning(Seq('b, 'c), 10),
+      OrderedDistribution(Seq('a.asc, 'b.asc, 'c.asc)),
+      false)
+
+    // TODO: We should check functional dependencies
+    /*
+    checkSatisfied(
+      ClusteredDistribution(Seq('b)),
+      ClusteredDistribution(Seq('b + 1)),
+      true)
+    */
+  }
+
+  test("RangePartitioning is the output partitioning") {
+    // Cases which do not need an exchange between two data properties.
+    checkSatisfied(
+      RangePartitioning(Seq('a.asc, 'b.asc, 'c.asc), 10),
+      UnspecifiedDistribution,
+      true)
+
+    checkSatisfied(
+      RangePartitioning(Seq('a.asc, 'b.asc, 'c.asc), 10),
+      OrderedDistribution(Seq('a.asc, 'b.asc, 'c.asc)),
+      true)
+
+    checkSatisfied(
+      RangePartitioning(Seq('a.asc, 'b.asc, 'c.asc), 10),
+      OrderedDistribution(Seq('a.asc, 'b.asc)),
+      true)
+
+    checkSatisfied(
+      RangePartitioning(Seq('a.asc, 'b.asc, 'c.asc), 10),
+      OrderedDistribution(Seq('a.asc, 'b.asc, 'c.asc, 'd.desc)),
+      true)
+
+    checkSatisfied(
+      RangePartitioning(Seq('a.asc, 'b.asc, 'c.asc), 10),
+      ClusteredDistribution(Seq('a, 'b, 'c)),
+      true)
+
+    checkSatisfied(
+      RangePartitioning(Seq('a.asc, 'b.asc, 'c.asc), 10),
+      ClusteredDistribution(Seq('c, 'b, 'a)),
+      true)
+
+    checkSatisfied(
+      RangePartitioning(Seq('a.asc, 'b.asc, 'c.asc), 10),
+      ClusteredDistribution(Seq('b, 'c, 'a, 'd)),
+      true)
+
+    // Cases which need an exchange between two data properties.
+    // TODO: We can have an optimization to first sort the dataset
+    // by a.asc and then sort b, and c in a partition. This optimization
+    // should tradeoff the benefit of a less number of Exchange operators
+    // and the parallelism.
+    checkSatisfied(
+      RangePartitioning(Seq('a.asc, 'b.asc, 'c.asc), 10),
+      OrderedDistribution(Seq('a.asc, 'b.desc, 'c.asc)),
+      false)
+
+    checkSatisfied(
+      RangePartitioning(Seq('a.asc, 'b.asc, 'c.asc), 10),
+      OrderedDistribution(Seq('b.asc, 'a.asc)),
+      false)
+
+    checkSatisfied(
+      RangePartitioning(Seq('a.asc, 'b.asc, 'c.asc), 10),
+      ClusteredDistribution(Seq('a, 'b)),
+      false)
+
+    checkSatisfied(
+      RangePartitioning(Seq('a.asc, 'b.asc, 'c.asc), 10),
+      ClusteredDistribution(Seq('c, 'd)),
+      false)
+
+    checkSatisfied(
+      RangePartitioning(Seq('a.asc, 'b.asc, 'c.asc), 10),
+      AllTuples,
+      false)
+  }
+}
\ No newline at end of file
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/ExpressionEvaluationSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/ExpressionEvaluationSuite.scala
new file mode 100644
index 0000000000..f06618ad11
--- /dev/null
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/ExpressionEvaluationSuite.scala
@@ -0,0 +1,115 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package expressions
+
+import org.scalatest.FunSuite
+
+import org.apache.spark.sql.catalyst.expressions._
+import org.apache.spark.sql.catalyst.types._
+
+/* Implict conversions */
+import org.apache.spark.sql.catalyst.dsl.expressions._
+
+class ExpressionEvaluationSuite extends FunSuite {
+
+  test("literals") {
+    assert((Literal(1) + Literal(1)).apply(null) === 2)
+  }
+
+  /**
+   * Checks for three-valued-logic.  Based on:
+   * http://en.wikipedia.org/wiki/Null_(SQL)#Comparisons_with_NULL_and_the_three-valued_logic_.283VL.29
+   *
+   * p       q       p OR q  p AND q  p = q
+   * True    True    True    True     True
+   * True    False   True    False    False
+   * True    Unknown True    Unknown  Unknown
+   * False   True    True    False    False
+   * False   False   False   False    True
+   * False   Unknown Unknown False    Unknown
+   * Unknown True    True    Unknown  Unknown
+   * Unknown False   Unknown False    Unknown
+   * Unknown Unknown Unknown Unknown  Unknown
+   *
+   * p       NOT p
+   * True    False
+   * False   True
+   * Unknown Unknown
+   */
+
+  val notTrueTable =
+    (true, false) ::
+    (false, true) ::
+    (null, null) :: Nil
+
+  test("3VL Not") {
+    notTrueTable.foreach {
+      case (v, answer) =>
+        val expr = Not(Literal(v, BooleanType))
+        val result = expr.apply(null)
+        if (result != answer)
+          fail(s"$expr should not evaluate to $result, expected: $answer")    }
+  }
+
+  booleanLogicTest("AND", _ && _,
+    (true,  true,  true) ::
+    (true,  false, false) ::
+    (true,  null,  null) ::
+    (false, true,  false) ::
+    (false, false, false) ::
+    (false, null,  false) ::
+    (null,  true,  null) ::
+    (null,  false, false) ::
+    (null,  null,  null) :: Nil)
+
+  booleanLogicTest("OR", _ || _,
+    (true,  true,  true) ::
+    (true,  false, true) ::
+    (true,  null,  true) ::
+    (false, true,  true) ::
+    (false, false, false) ::
+    (false, null,  null) ::
+    (null,  true,  true) ::
+    (null,  false, null) ::
+    (null,  null,  null) :: Nil)
+
+  booleanLogicTest("=", _ === _,
+    (true,  true,  true) ::
+    (true,  false, false) ::
+    (true,  null,  null) ::
+    (false, true,  false) ::
+    (false, false, true) ::
+    (false, null,  null) ::
+    (null,  true,  null) ::
+    (null,  false, null) ::
+    (null,  null,  null) :: Nil)
+
+  def booleanLogicTest(name: String, op: (Expression, Expression) => Expression,  truthTable: Seq[(Any, Any, Any)]) {
+    test(s"3VL $name") {
+      truthTable.foreach {
+        case (l,r,answer) =>
+          val expr = op(Literal(l, BooleanType), Literal(r, BooleanType))
+          val result = expr.apply(null)
+          if (result != answer)
+            fail(s"$expr should not evaluate to $result, expected: $answer")
+      }
+    }
+  }
+}
\ No newline at end of file
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/HiveTypeCoercionSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/HiveTypeCoercionSuite.scala
new file mode 100644
index 0000000000..f595bf7e44
--- /dev/null
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/HiveTypeCoercionSuite.scala
@@ -0,0 +1,74 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package analysis
+
+import org.scalatest.FunSuite
+
+import catalyst.types._
+
+
+class HiveTypeCoercionSuite extends FunSuite {
+
+  val rules = new HiveTypeCoercion { }
+  import rules._
+
+  test("tightest common bound for numeric and boolean types") {
+    def widenTest(t1: DataType, t2: DataType, tightestCommon: Option[DataType]) {
+      var found = WidenTypes.findTightestCommonType(t1, t2)
+      assert(found == tightestCommon,
+        s"Expected $tightestCommon as tightest common type for $t1 and $t2, found $found")
+      // Test both directions to make sure the widening is symmetric.
+      found = WidenTypes.findTightestCommonType(t2, t1)
+      assert(found == tightestCommon,
+        s"Expected $tightestCommon as tightest common type for $t2 and $t1, found $found")
+    }
+
+    // Boolean
+    widenTest(NullType, BooleanType, Some(BooleanType))
+    widenTest(BooleanType, BooleanType, Some(BooleanType))
+    widenTest(IntegerType, BooleanType, None)
+    widenTest(LongType, BooleanType, None)
+
+    // Integral
+    widenTest(NullType, ByteType, Some(ByteType))
+    widenTest(NullType, IntegerType, Some(IntegerType))
+    widenTest(NullType, LongType, Some(LongType))
+    widenTest(ShortType, IntegerType, Some(IntegerType))
+    widenTest(ShortType, LongType, Some(LongType))
+    widenTest(IntegerType, LongType, Some(LongType))
+    widenTest(LongType, LongType, Some(LongType))
+
+    // Floating point
+    widenTest(NullType, FloatType, Some(FloatType))
+    widenTest(NullType, DoubleType, Some(DoubleType))
+    widenTest(FloatType, DoubleType, Some(DoubleType))
+    widenTest(FloatType, FloatType, Some(FloatType))
+    widenTest(DoubleType, DoubleType, Some(DoubleType))
+
+    // Integral mixed with floating point.
+    widenTest(NullType, FloatType, Some(FloatType))
+    widenTest(NullType, DoubleType, Some(DoubleType))
+    widenTest(IntegerType, FloatType, Some(FloatType))
+    widenTest(IntegerType, DoubleType, Some(DoubleType))
+    widenTest(IntegerType, DoubleType, Some(DoubleType))
+    widenTest(LongType, FloatType, Some(FloatType))
+    widenTest(LongType, DoubleType, Some(DoubleType))
+  }
+}
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/RuleExecutorSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/RuleExecutorSuite.scala
new file mode 100644
index 0000000000..ff7c15b718
--- /dev/null
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/RuleExecutorSuite.scala
@@ -0,0 +1,57 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package trees
+
+import org.scalatest.FunSuite
+
+import expressions._
+import rules._
+
+class RuleExecutorSuite extends FunSuite {
+  object DecrementLiterals extends Rule[Expression] {
+    def apply(e: Expression): Expression = e transform {
+      case IntegerLiteral(i) if i > 0 => Literal(i - 1)
+    }
+  }
+
+  test("only once") {
+    object ApplyOnce extends RuleExecutor[Expression] {
+      val batches = Batch("once", Once, DecrementLiterals) :: Nil
+    }
+
+    assert(ApplyOnce(Literal(10)) === Literal(9))
+  }
+
+  test("to fixed point") {
+    object ToFixedPoint extends RuleExecutor[Expression] {
+      val batches = Batch("fixedPoint", FixedPoint(100), DecrementLiterals) :: Nil
+    }
+
+    assert(ToFixedPoint(Literal(10)) === Literal(0))
+  }
+
+  test("to maxIterations") {
+    object ToFixedPoint extends RuleExecutor[Expression] {
+      val batches = Batch("fixedPoint", FixedPoint(10), DecrementLiterals) :: Nil
+    }
+
+    assert(ToFixedPoint(Literal(100)) === Literal(90))
+  }
+}
\ No newline at end of file
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/TreeNodeSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/TreeNodeSuite.scala
new file mode 100644
index 0000000000..98bb090c29
--- /dev/null
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/TreeNodeSuite.scala
@@ -0,0 +1,81 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package trees
+
+import scala.collection.mutable.ArrayBuffer
+
+import expressions._
+
+import org.scalatest.{FunSuite}
+
+class TreeNodeSuite extends FunSuite {
+
+  test("top node changed") {
+    val after = Literal(1) transform { case Literal(1, _) => Literal(2) }
+    assert(after === Literal(2))
+  }
+
+  test("one child changed") {
+    val before = Add(Literal(1), Literal(2))
+    val after = before transform { case Literal(2, _) => Literal(1) }
+
+    assert(after === Add(Literal(1), Literal(1)))
+  }
+
+  test("no change") {
+    val before = Add(Literal(1), Add(Literal(2), Add(Literal(3), Literal(4))))
+    val after = before transform { case Literal(5, _) => Literal(1)}
+
+    assert(before === after)
+    assert(before.map(_.id) === after.map(_.id))
+  }
+
+  test("collect") {
+    val tree = Add(Literal(1), Add(Literal(2), Add(Literal(3), Literal(4))))
+    val literals = tree collect {case l: Literal => l}
+
+    assert(literals.size === 4)
+    (1 to 4).foreach(i => assert(literals contains Literal(i)))
+  }
+
+  test("pre-order transform") {
+    val actual = new ArrayBuffer[String]()
+    val expected = Seq("+", "1", "*", "2", "-", "3", "4")
+    val expression = Add(Literal(1), Multiply(Literal(2), Subtract(Literal(3), Literal(4))))
+    expression transformDown {
+      case b: BinaryExpression => {actual.append(b.symbol); b}
+      case l: Literal => {actual.append(l.toString); l}
+    }
+
+    assert(expected === actual)
+  }
+
+  test("post-order transform") {
+    val actual = new ArrayBuffer[String]()
+    val expected = Seq("1", "2", "3", "4", "-", "*", "+")
+    val expression = Add(Literal(1), Multiply(Literal(2), Subtract(Literal(3), Literal(4))))
+    expression transformUp {
+      case b: BinaryExpression => {actual.append(b.symbol); b}
+      case l: Literal => {actual.append(l.toString); l}
+    }
+
+    assert(expected === actual)
+  }
+}
\ No newline at end of file
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/optimizer/ConstantFoldingSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/optimizer/ConstantFoldingSuite.scala
new file mode 100644
index 0000000000..7ce42b2b0a
--- /dev/null
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/optimizer/ConstantFoldingSuite.scala
@@ -0,0 +1,176 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql
+package catalyst
+package optimizer
+
+import types.IntegerType
+import util._
+import plans.logical.{LogicalPlan, LocalRelation}
+import rules._
+import expressions._
+import dsl.plans._
+import dsl.expressions._
+
+class ConstantFoldingSuite extends OptimizerTest {
+
+  object Optimize extends RuleExecutor[LogicalPlan] {
+    val batches =
+      Batch("Subqueries", Once,
+        EliminateSubqueries) ::
+      Batch("ConstantFolding", Once,
+        ConstantFolding,
+        BooleanSimplification) :: Nil
+  }
+
+  val testRelation = LocalRelation('a.int, 'b.int, 'c.int)
+
+  test("eliminate subqueries") {
+    val originalQuery =
+      testRelation
+        .subquery('y)
+        .select('a)
+
+    val optimized = Optimize(originalQuery.analyze)
+    val correctAnswer =
+      testRelation
+        .select('a.attr)
+        .analyze
+
+    comparePlans(optimized, correctAnswer)
+  }
+
+  /**
+   * Unit tests for constant folding in expressions.
+   */
+  test("Constant folding test: expressions only have literals") {
+    val originalQuery =
+      testRelation
+        .select(
+          Literal(2) + Literal(3) + Literal(4) as Symbol("2+3+4"),
+          Literal(2) * Literal(3) + Literal(4) as Symbol("2*3+4"),
+          Literal(2) * (Literal(3) + Literal(4)) as Symbol("2*(3+4)"))
+        .where(
+          Literal(1) === Literal(1) &&
+          Literal(2) > Literal(3) ||
+          Literal(3) > Literal(2) )
+        .groupBy(
+          Literal(2) * Literal(3) - Literal(6) / (Literal(4) - Literal(2))
+        )(Literal(9) / Literal(3) as Symbol("9/3"))
+
+    val optimized = Optimize(originalQuery.analyze)
+
+    val correctAnswer =
+      testRelation
+        .select(
+          Literal(9) as Symbol("2+3+4"),
+          Literal(10) as Symbol("2*3+4"),
+          Literal(14) as Symbol("2*(3+4)"))
+        .where(Literal(true))
+        .groupBy(Literal(3))(Literal(3) as Symbol("9/3"))
+        .analyze
+
+    comparePlans(optimized, correctAnswer)
+  }
+
+  test("Constant folding test: expressions have attribute references and literals in " +
+    "arithmetic operations") {
+    val originalQuery =
+      testRelation
+        .select(
+          Literal(2) + Literal(3) + 'a as Symbol("c1"),
+          'a + Literal(2) + Literal(3) as Symbol("c2"),
+          Literal(2) * 'a + Literal(4) as Symbol("c3"),
+          'a * (Literal(3) + Literal(4)) as Symbol("c4"))
+
+    val optimized = Optimize(originalQuery.analyze)
+
+    val correctAnswer =
+      testRelation
+        .select(
+          Literal(5) + 'a as Symbol("c1"),
+          'a + Literal(2) + Literal(3) as Symbol("c2"),
+          Literal(2) * 'a + Literal(4) as Symbol("c3"),
+          'a * (Literal(7)) as Symbol("c4"))
+        .analyze
+
+    comparePlans(optimized, correctAnswer)
+  }
+
+  test("Constant folding test: expressions have attribute references and literals in " +
+    "predicates") {
+    val originalQuery =
+      testRelation
+        .where(
+          (('a > 1 && Literal(1) === Literal(1)) ||
+           ('a < 10 && Literal(1) === Literal(2)) ||
+           (Literal(1) === Literal(1) && 'b > 1) ||
+           (Literal(1) === Literal(2) && 'b < 10)) &&
+           (('a > 1 || Literal(1) === Literal(1)) &&
+            ('a < 10 || Literal(1) === Literal(2)) &&
+            (Literal(1) === Literal(1) || 'b > 1) &&
+            (Literal(1) === Literal(2) || 'b < 10)))
+
+    val optimized = Optimize(originalQuery.analyze)
+
+    val correctAnswer =
+      testRelation
+        .where(('a > 1 || 'b > 1) && ('a < 10 && 'b < 10))
+        .analyze
+
+    comparePlans(optimized, correctAnswer)
+  }
+
+  test("Constant folding test: expressions have foldable functions") {
+    val originalQuery =
+      testRelation
+        .select(
+          Cast(Literal("2"), IntegerType) + Literal(3) + 'a as Symbol("c1"),
+          Coalesce(Seq(Cast(Literal("abc"), IntegerType), Literal(3))) as Symbol("c2"))
+
+    val optimized = Optimize(originalQuery.analyze)
+
+    val correctAnswer =
+      testRelation
+        .select(
+          Literal(5) + 'a as Symbol("c1"),
+          Literal(3) as Symbol("c2"))
+        .analyze
+
+    comparePlans(optimized, correctAnswer)
+  }
+
+  test("Constant folding test: expressions have nonfoldable functions") {
+    val originalQuery =
+      testRelation
+        .select(
+          Rand + Literal(1) as Symbol("c1"),
+          Sum('a) as Symbol("c2"))
+
+    val optimized = Optimize(originalQuery.analyze)
+
+    val correctAnswer =
+      testRelation
+        .select(
+          Rand + Literal(1.0) as Symbol("c1"),
+          Sum('a) as Symbol("c2"))
+        .analyze
+
+    comparePlans(optimized, correctAnswer)
+  }
+}
\ No newline at end of file
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/optimizer/FilterPushdownSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/optimizer/FilterPushdownSuite.scala
new file mode 100644
index 0000000000..cd611b3fb3
--- /dev/null
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/optimizer/FilterPushdownSuite.scala
@@ -0,0 +1,222 @@
+package org.apache.spark.sql
+package catalyst
+package optimizer
+
+import expressions._
+import plans.logical._
+import rules._
+import util._
+
+import dsl.plans._
+import dsl.expressions._
+
+class FilterPushdownSuite extends OptimizerTest {
+
+  object Optimize extends RuleExecutor[LogicalPlan] {
+    val batches =
+      Batch("Subqueries", Once,
+        EliminateSubqueries) ::
+      Batch("Filter Pushdown", Once,
+        EliminateSubqueries,
+        CombineFilters,
+        PushPredicateThroughProject,
+        PushPredicateThroughInnerJoin) :: Nil
+  }
+
+  val testRelation = LocalRelation('a.int, 'b.int, 'c.int)
+
+  // This test already passes.
+  test("eliminate subqueries") {
+    val originalQuery =
+      testRelation
+        .subquery('y)
+        .select('a)
+
+    val optimized = Optimize(originalQuery.analyze)
+    val correctAnswer =
+      testRelation
+        .select('a.attr)
+        .analyze
+
+    comparePlans(optimized, correctAnswer)
+  }
+
+  // After this line is unimplemented.
+  test("simple push down") {
+    val originalQuery =
+      testRelation
+        .select('a)
+        .where('a === 1)
+
+    val optimized = Optimize(originalQuery.analyze)
+    val correctAnswer =
+      testRelation
+        .where('a === 1)
+        .select('a)
+        .analyze
+
+    comparePlans(optimized, correctAnswer)
+  }
+
+  test("can't push without rewrite") {
+    val originalQuery =
+      testRelation
+        .select('a + 'b as 'e)
+        .where('e === 1)
+        .analyze
+
+    val optimized = Optimize(originalQuery.analyze)
+    val correctAnswer =
+      testRelation
+        .where('a + 'b === 1)
+        .select('a + 'b as 'e)
+        .analyze
+
+    comparePlans(optimized, correctAnswer)
+  }
+
+  test("filters: combines filters") {
+    val originalQuery = testRelation
+      .select('a)
+      .where('a === 1)
+      .where('a === 2)
+
+    val optimized = Optimize(originalQuery.analyze)
+    val correctAnswer =
+      testRelation
+        .where('a === 1 && 'a === 2)
+        .select('a).analyze
+
+
+    comparePlans(optimized, correctAnswer)
+  }
+
+
+  test("joins: push to either side") {
+    val x = testRelation.subquery('x)
+    val y = testRelation.subquery('y)
+
+    val originalQuery = {
+      x.join(y)
+        .where("x.b".attr === 1)
+        .where("y.b".attr === 2)
+    }
+
+    val optimized = Optimize(originalQuery.analyze)
+    val left = testRelation.where('b === 1)
+    val right = testRelation.where('b === 2)
+    val correctAnswer =
+      left.join(right).analyze
+
+    comparePlans(optimized, correctAnswer)
+  }
+
+  test("joins: push to one side") {
+    val x = testRelation.subquery('x)
+    val y = testRelation.subquery('y)
+
+    val originalQuery = {
+      x.join(y)
+        .where("x.b".attr === 1)
+    }
+
+    val optimized = Optimize(originalQuery.analyze)
+    val left = testRelation.where('b === 1)
+    val right = testRelation
+    val correctAnswer =
+      left.join(right).analyze
+
+    comparePlans(optimized, correctAnswer)
+  }
+
+  test("joins: rewrite filter to push to either side") {
+    val x = testRelation.subquery('x)
+    val y = testRelation.subquery('y)
+
+    val originalQuery = {
+      x.join(y)
+        .where("x.b".attr === 1 && "y.b".attr === 2)
+    }
+
+    val optimized = Optimize(originalQuery.analyze)
+    val left = testRelation.where('b === 1)
+    val right = testRelation.where('b === 2)
+    val correctAnswer =
+      left.join(right).analyze
+
+    comparePlans(optimized, correctAnswer)
+  }
+
+  test("joins: can't push down") {
+    val x = testRelation.subquery('x)
+    val y = testRelation.subquery('y)
+
+    val originalQuery = {
+      x.join(y, condition = Some("x.b".attr === "y.b".attr))
+    }
+    val optimized = Optimize(originalQuery.analyze)
+
+    comparePlans(optimizer.EliminateSubqueries(originalQuery.analyze), optimized)
+  }
+
+  test("joins: conjunctive predicates") {
+    val x = testRelation.subquery('x)
+    val y = testRelation.subquery('y)
+
+    val originalQuery = {
+      x.join(y)
+        .where(("x.b".attr === "y.b".attr) && ("x.a".attr === 1) && ("y.a".attr === 1))
+    }
+
+    val optimized = Optimize(originalQuery.analyze)
+    val left = testRelation.where('a === 1).subquery('x)
+    val right = testRelation.where('a === 1).subquery('y)
+    val correctAnswer =
+      left.join(right, condition = Some("x.b".attr === "y.b".attr))
+        .analyze
+
+    comparePlans(optimized, optimizer.EliminateSubqueries(correctAnswer))
+  }
+
+  test("joins: conjunctive predicates #2") {
+    val x = testRelation.subquery('x)
+    val y = testRelation.subquery('y)
+
+    val originalQuery = {
+      x.join(y)
+        .where(("x.b".attr === "y.b".attr) && ("x.a".attr === 1))
+    }
+
+    val optimized = Optimize(originalQuery.analyze)
+    val left = testRelation.where('a === 1).subquery('x)
+    val right = testRelation.subquery('y)
+    val correctAnswer =
+      left.join(right, condition = Some("x.b".attr === "y.b".attr))
+        .analyze
+
+    comparePlans(optimized, optimizer.EliminateSubqueries(correctAnswer))
+  }
+
+  test("joins: conjunctive predicates #3") {
+    val x = testRelation.subquery('x)
+    val y = testRelation.subquery('y)
+    val z = testRelation.subquery('z)
+
+    val originalQuery = {
+      z.join(x.join(y))
+        .where(("x.b".attr === "y.b".attr) && ("x.a".attr === 1) && ("z.a".attr >= 3) && ("z.a".attr === "x.b".attr))
+    }
+
+    val optimized = Optimize(originalQuery.analyze)
+    val lleft = testRelation.where('a >= 3).subquery('z)
+    val left = testRelation.where('a === 1).subquery('x)
+    val right = testRelation.subquery('y)
+    val correctAnswer =
+      lleft.join(
+        left.join(right, condition = Some("x.b".attr === "y.b".attr)),
+          condition = Some("z.a".attr === "x.b".attr))
+        .analyze
+
+    comparePlans(optimized, optimizer.EliminateSubqueries(correctAnswer))
+  }
+}
\ No newline at end of file
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/optimizer/OptimizerTest.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/optimizer/OptimizerTest.scala
new file mode 100644
index 0000000000..7b3653d0f9
--- /dev/null
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/optimizer/OptimizerTest.scala
@@ -0,0 +1,44 @@
+package org.apache.spark.sql
+package catalyst
+package optimizer
+
+import org.scalatest.FunSuite
+
+import types.IntegerType
+import util._
+import plans.logical.{LogicalPlan, LocalRelation}
+import expressions._
+import dsl._
+
+/* Implicit conversions for creating query plans */
+
+/**
+ * Provides helper methods for comparing plans produced by optimization rules with the expected
+ * result
+ */
+class OptimizerTest extends FunSuite {
+
+  /**
+   * Since attribute references are given globally unique ids during analysis,
+   * we must normalize them to check if two different queries are identical.
+   */
+  protected def normalizeExprIds(plan: LogicalPlan) = {
+    val minId = plan.flatMap(_.expressions.flatMap(_.references).map(_.exprId.id)).min
+    plan transformAllExpressions {
+      case a: AttributeReference =>
+        AttributeReference(a.name, a.dataType, a.nullable)(exprId = ExprId(a.exprId.id - minId))
+    }
+  }
+
+  /** Fails the test if the two plans do not match */
+  protected def comparePlans(plan1: LogicalPlan, plan2: LogicalPlan) {
+    val normalized1 = normalizeExprIds(plan1)
+    val normalized2 = normalizeExprIds(plan2)
+    if (normalized1 != normalized2)
+      fail(
+        s"""
+          |== FAIL: Plans do not match ===
+          |${sideBySide(normalized1.treeString, normalized2.treeString).mkString("\n")}
+        """.stripMargin)
+  }
+}
\ No newline at end of file