[SPARK-6247][SQL] Fix resolution of ambiguous joins caused by new aliases

We need to handle ambiguous `exprId`s that are produced by new aliases as well as those caused by leaf nodes (`MultiInstanceRelation`).

Attempting to fix this revealed a bug in `equals` for `Alias` as these objects were comparing equal even when the expression ids did not match. Additionally, `LocalRelation` did not correctly provide statistics, and some tests in `catalyst` and `hive` were not using the helper functions for comparing plans.

Based on #4991 by chenghao-intel

Author: Michael Armbrust <michael@databricks.com>

Closes #5062 from marmbrus/selfJoins and squashes the following commits:

8e9b84b [Michael Armbrust] check qualifier too
8038a36 [Michael Armbrust] handle aggs too
0b9c687 [Michael Armbrust] fix more tests
c3c574b [Michael Armbrust] revert change.
725f1ab [Michael Armbrust] add statistics
a925d08 [Michael Armbrust] check for conflicting attributes in join resolution
b022ef7 [Michael Armbrust] Handle project aliases.
d8caa40 [Michael Armbrust] test case: SPARK-6247
f9c67c2 [Michael Armbrust] Check for duplicate attributes in join resolution.
898af73 [Michael Armbrust] Fix Alias equality.

1 files changed, 3 insertions, 1 deletions

diff --git a/sql/hive/src/test/scala/org/apache/spark/sql/catalyst/plans/PlanTest.scala b/sql/hive/src/test/scala/org/apache/spark/sql/catalyst/plans/PlanTest.scala
index 44ee5ab597..98f1c0e69e 100644
--- a/sql/hive/src/test/scala/org/apache/spark/sql/catalyst/plans/PlanTest.scala
+++ b/sql/hive/src/test/scala/org/apache/spark/sql/catalyst/plans/PlanTest.scala
@@ -17,7 +17,7 @@
 
 package org.apache.spark.sql.catalyst.plans
 
-import org.apache.spark.sql.catalyst.expressions.{AttributeReference, ExprId}
+import org.apache.spark.sql.catalyst.expressions.{Alias, AttributeReference, ExprId}
 import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan
 import org.apache.spark.sql.catalyst.util._
 import org.scalatest.FunSuite
@@ -38,6 +38,8 @@ class PlanTest extends FunSuite {
     plan transformAllExpressions {
       case a: AttributeReference =>
         AttributeReference(a.name, a.dataType, a.nullable)(exprId = ExprId(0))
+      case a: Alias =>
+        Alias(a.child, a.name)(exprId = ExprId(0))
     }
   }