[SPARK-11197][SQL] run SQL on files directly

This PR introduce a new feature to run SQL directly on files without create a table, for example:

```
select id from json.`path/to/json/files` as j
```

Author: Davies Liu <davies@databricks.com>

Closes #9173 from davies/source.

3 files changed, 12 insertions, 3 deletions

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
index 016dc293f4..beabacfc88 100644
--- 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
@@ -256,7 +256,7 @@ class Analyzer(
         catalog.lookupRelation(u.tableIdentifier, u.alias)
       } catch {
         case _: NoSuchTableException =>
-          u.failAnalysis(s"Table Not Found: ${u.tableName}")
+          u.failAnalysis(s"Table not found: ${u.tableName}")
       }
     }
 
@@ -264,7 +264,13 @@ class Analyzer(
       case i @ InsertIntoTable(u: UnresolvedRelation, _, _, _, _) =>
         i.copy(table = EliminateSubQueries(getTable(u)))
       case u: UnresolvedRelation =>
-        getTable(u)
+        try {
+          getTable(u)
+        } catch {
+          case _: AnalysisException if u.tableIdentifier.database.isDefined =>
+            // delay the exception into CheckAnalysis, then it could be resolved as data source.
+            u
+        }
     }
   }
 
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/CheckAnalysis.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/CheckAnalysis.scala
index 7701fd0451..ab215407f7 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/CheckAnalysis.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/CheckAnalysis.scala
@@ -49,6 +49,9 @@ trait CheckAnalysis {
     plan.foreachUp {
       case p if p.analyzed => // Skip already analyzed sub-plans
 
+      case u: UnresolvedRelation =>
+        u.failAnalysis(s"Table not found: ${u.tableIdentifier}")
+
       case operator: LogicalPlan =>
         operator transformExpressionsUp {
           case a: Attribute if !a.resolved =>
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisSuite.scala
index 24af8483a7..0a1fa74bed 100644
--- a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisSuite.scala
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisSuite.scala
@@ -78,7 +78,7 @@ class AnalysisSuite extends AnalysisTest {
 
   test("resolve relations") {
     assertAnalysisError(
-      UnresolvedRelation(TableIdentifier("tAbLe"), None), Seq("Table Not Found: tAbLe"))
+      UnresolvedRelation(TableIdentifier("tAbLe"), None), Seq("Table not found: tAbLe"))
 
     checkAnalysis(UnresolvedRelation(TableIdentifier("TaBlE"), None), testRelation)