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The following commit(s) were added to refs/heads/master by this push:
     new c96fef2ea55 [SPARK-45580][SQL] Handle case where a nested subquery 
becomes an existence join
c96fef2ea55 is described below

commit c96fef2ea55ee85ac66905584e9dee31471de9f1
Author: Bruce Robbins <bersprock...@gmail.com>
AuthorDate: Wed Dec 6 10:55:15 2023 -0800

    [SPARK-45580][SQL] Handle case where a nested subquery becomes an existence 
join
    
    ### What changes were proposed in this pull request?
    
    In `RewritePredicateSubquery`, prune existence flags from the final join 
when `rewriteExistentialExpr` returns an existence join. This change prunes the 
flags (attributes with the name "exists") by adding a `Project` node.
    
    For example:
    ```
    Join LeftSemi, ((a#13 = c1#15) OR exists#19)
    :- Join ExistenceJoin(exists#19), (a#13 = col1#17)
    :  :- LocalRelation [a#13]
    :  +- LocalRelation [col1#17]
    +- LocalRelation [c1#15]
    ```
    becomes
    ```
    Project [a#13]
    +- Join LeftSemi, ((a#13 = c1#15) OR exists#19)
       :- Join ExistenceJoin(exists#19), (a#13 = col1#17)
       :  :- LocalRelation [a#13]
       :  +- LocalRelation [col1#17]
       +- LocalRelation [c1#15]
    ```
    This change always adds the `Project` node, whether 
`rewriteExistentialExpr` returns an existence join or not. In the case when 
`rewriteExistentialExpr` does not return an existence join, 
`RemoveNoopOperators` will remove the unneeded `Project` node.
    
    ### Why are the changes needed?
    
    This query returns an extraneous boolean column when run in spark-sql:
    ```
    create or replace temp view t1(a) as values (1), (2), (3), (7);
    create or replace temp view t2(c1) as values (1), (2), (3);
    create or replace temp view t3(col1) as values (3), (9);
    
    select *
    from t1
    where exists (
      select c1
      from t2
      where a = c1
      or a in (select col1 from t3)
    );
    
    1       false
    2       false
    3       true
    ```
    (Note: the above query will not have the extraneous boolean column when run 
from the Dataset API. That is because the Dataset API truncates the rows based 
on the schema of the analyzed plan. The bug occurs during optimization).
    
    This query fails when run in either spark-sql or using the Dataset API:
    ```
    select (
      select *
      from t1
      where exists (
        select c1
        from t2
        where a = c1
        or a in (select col1 from t3)
      )
      limit 1
    )
    from range(1);
    
    java.lang.AssertionError: assertion failed: Expects 1 field, but got 2; 
something went wrong in analysis
    ```
    
    ### Does this PR introduce _any_ user-facing change?
    
    No, except for the removal of the extraneous boolean flag and the fix to 
the error condition.
    
    ### How was this patch tested?
    
    New unit test.
    
    ### Was this patch authored or co-authored using generative AI tooling?
    
    No.
    
    Closes #44193 from bersprockets/schema_change.
    
    Authored-by: Bruce Robbins <bersprock...@gmail.com>
    Signed-off-by: Dongjoon Hyun <dh...@apple.com>
---
 .../spark/sql/catalyst/optimizer/subquery.scala    |  9 +++--
 .../scala/org/apache/spark/sql/SubquerySuite.scala | 46 ++++++++++++++++++++++
 2 files changed, 52 insertions(+), 3 deletions(-)

diff --git 
a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/subquery.scala
 
b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/subquery.scala
index 1f1a16e9093..6ca2cb79aaf 100644
--- 
a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/subquery.scala
+++ 
b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/subquery.scala
@@ -132,19 +132,22 @@ object RewritePredicateSubquery extends Rule[LogicalPlan] 
with PredicateHelper {
       withSubquery.foldLeft(newFilter) {
         case (p, Exists(sub, _, _, conditions, subHint)) =>
           val (joinCond, outerPlan) = rewriteExistentialExpr(conditions, p)
-          buildJoin(outerPlan, rewriteDomainJoinsIfPresent(outerPlan, sub, 
joinCond),
+          val join = buildJoin(outerPlan, 
rewriteDomainJoinsIfPresent(outerPlan, sub, joinCond),
             LeftSemi, joinCond, subHint)
+          Project(p.output, join)
         case (p, Not(Exists(sub, _, _, conditions, subHint))) =>
           val (joinCond, outerPlan) = rewriteExistentialExpr(conditions, p)
-          buildJoin(outerPlan, rewriteDomainJoinsIfPresent(outerPlan, sub, 
joinCond),
+          val join = buildJoin(outerPlan, 
rewriteDomainJoinsIfPresent(outerPlan, sub, joinCond),
             LeftAnti, joinCond, subHint)
+          Project(p.output, join)
         case (p, InSubquery(values, ListQuery(sub, _, _, _, conditions, 
subHint))) =>
           // Deduplicate conflicting attributes if any.
           val newSub = dedupSubqueryOnSelfJoin(p, sub, Some(values))
           val inConditions = values.zip(newSub.output).map(EqualTo.tupled)
           val (joinCond, outerPlan) = rewriteExistentialExpr(inConditions ++ 
conditions, p)
-          Join(outerPlan, rewriteDomainJoinsIfPresent(outerPlan, newSub, 
joinCond),
+          val join = Join(outerPlan, rewriteDomainJoinsIfPresent(outerPlan, 
newSub, joinCond),
             LeftSemi, joinCond, JoinHint(None, subHint))
+          Project(p.output, join)
         case (p, Not(InSubquery(values, ListQuery(sub, _, _, _, conditions, 
subHint)))) =>
           // This is a NULL-aware (left) anti join (NAAJ) e.g. col NOT IN expr
           // Construct the condition. A NULL in one of the conditions is 
regarded as a positive
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/SubquerySuite.scala 
b/sql/core/src/test/scala/org/apache/spark/sql/SubquerySuite.scala
index d82fba82c1a..e1169dd06bd 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/SubquerySuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/SubquerySuite.scala
@@ -2735,4 +2735,50 @@ class SubquerySuite extends QueryTest
         Row(1, "a", 3) :: Row(2, "a", 3) :: Row(3, "a", 3) :: Nil)
     }
   }
+
+  test("SPARK-45580: Handle case where a nested subquery becomes an existence 
join") {
+    withTempView("t1", "t2", "t3") {
+      Seq((1), (2), (3), (7)).toDF("a").persist().createOrReplaceTempView("t1")
+      Seq((1), (2), (3)).toDF("c1").persist().createOrReplaceTempView("t2")
+      Seq((3), (9)).toDF("col1").persist().createOrReplaceTempView("t3")
+
+      val query1 =
+        """
+          |SELECT *
+          |FROM t1
+          |WHERE EXISTS (
+          |  SELECT c1
+          |  FROM t2
+          |  WHERE a = c1
+          |  OR a IN (SELECT col1 FROM t3)
+          |)""".stripMargin
+      val df1 = sql(query1)
+      checkAnswer(df1, Row(1) :: Row(2) :: Row(3) :: Nil)
+
+      val query2 =
+        """
+          |SELECT *
+          |FROM t1
+          |WHERE a IN (
+          |  SELECT c1
+          |  FROM t2
+          |  where a IN (SELECT col1 FROM t3)
+          |)""".stripMargin
+      val df2 = sql(query2)
+      checkAnswer(df2, Row(3))
+
+      val query3 =
+        """
+          |SELECT *
+          |FROM t1
+          |WHERE NOT EXISTS (
+          |  SELECT c1
+          |  FROM t2
+          |  WHERE a = c1
+          |  OR a IN (SELECT col1 FROM t3)
+          |)""".stripMargin
+      val df3 = sql(query3)
+      checkAnswer(df3, Row(7))
+    }
+  }
 }


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