[SPARK-17100] [SQL] fix Python udf in filter on top of outer join

## What changes were proposed in this pull request?

In optimizer, we try to evaluate the condition to see whether it's nullable or not, but some expressions are not evaluable, we should check that before evaluate it.

## How was this patch tested?

Added regression tests.

Author: Davies Liu <davies@databricks.com>

Closes #15103 from davies/udf_join.

1 files changed, 3 insertions, 1 deletions

diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/joins.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/joins.scala
index 1621bffd61..2626057e49 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/joins.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/joins.scala
@@ -109,7 +109,9 @@ object EliminateOuterJoin extends Rule[LogicalPlan] with PredicateHelper {
     if (!e.deterministic || SubqueryExpression.hasCorrelatedSubquery(e)) return false
     val attributes = e.references.toSeq
     val emptyRow = new GenericInternalRow(attributes.length)
-    val v = BindReferences.bindReference(e, attributes).eval(emptyRow)
+    val boundE = BindReferences.bindReference(e, attributes)
+    if (boundE.find(_.isInstanceOf[Unevaluable]).isDefined) return false
+    val v = boundE.eval(emptyRow)
     v == null || v == false
   }