[SPARK-1889] [SQL] Apply splitConjunctivePredicates to join condition while finding join ke...

...ys.

When tables are equi-joined by multiple-keys `HashJoin` should be used, but `CartesianProduct` and then `Filter` are used.
The join keys are paired by `And` expression so we need to apply `splitConjunctivePredicates` to join condition while finding join keys.

Author: Takuya UESHIN <ueshin@happy-camper.st>

Closes #836 from ueshin/issues/SPARK-1889 and squashes the following commits:

fe1c387 [Takuya UESHIN] Apply splitConjunctivePredicates to join condition while finding join keys.

1 files changed, 18 insertions, 1 deletions

diff --git a/sql/core/src/test/scala/org/apache/spark/sql/execution/PlannerSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/execution/PlannerSuite.scala
index e24c74a7a5..c563d63627 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/execution/PlannerSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/execution/PlannerSuite.scala
@@ -21,7 +21,7 @@ import org.scalatest.FunSuite
 
 import org.apache.spark.sql.TestData._
 import org.apache.spark.sql.catalyst.expressions._
-import org.apache.spark.sql.catalyst.plans.logical
+import org.apache.spark.sql.catalyst.plans._
 import org.apache.spark.sql.execution
 import org.apache.spark.sql.test.TestSQLContext._
 import org.apache.spark.sql.test.TestSQLContext.planner._
@@ -57,4 +57,21 @@ class PlannerSuite extends FunSuite {
     val planned = PartialAggregation(query)
     assert(planned.isEmpty)
   }
+
+  test("equi-join is hash-join") {
+    val x = testData2.as('x)
+    val y = testData2.as('y)
+    val join = x.join(y, Inner, Some("x.a".attr === "y.a".attr)).queryExecution.analyzed
+    val planned = planner.HashJoin(join)
+    assert(planned.size === 1)
+  }
+
+  test("multiple-key equi-join is hash-join") {
+    val x = testData2.as('x)
+    val y = testData2.as('y)
+    val join = x.join(y, Inner,
+      Some("x.a".attr === "y.a".attr && "x.b".attr === "y.b".attr)).queryExecution.analyzed
+    val planned = planner.HashJoin(join)
+    assert(planned.size === 1)
+  }
 }