viirya commented on a change in pull request #31595:
URL: https://github.com/apache/spark/pull/31595#discussion_r580858078
##########
File path:
sql/core/src/test/scala/org/apache/spark/sql/DataFrameSetOperationsSuite.scala
##########
@@ -808,6 +813,53 @@ class DataFrameSetOperationsSuite extends QueryTest with
SharedSparkSession {
// scalastyle:on
checkAnswer(union, row1 :: row2 :: Nil)
}
+
+ test("SPARK-34474: Remove unnecessary Union under Distinct") {
+ Seq(RemoveNoopUnion.ruleName, "").map { ruleName =>
+ withSQLConf(SQLConf.OPTIMIZER_EXCLUDED_RULES.key -> ruleName) {
+ val distinctUnionDF1 = testData.union(testData).distinct()
+ checkAnswer(distinctUnionDF1, testData.distinct())
+
+
+ val distinctUnionDF2 =
testData.union(testData).dropDuplicates(Seq("key"))
+ checkAnswer(distinctUnionDF2, testData.dropDuplicates(Seq("key")))
+
+ val distinctUnionDF3 = sql(
+ """
+ |select key, value from testData
+ |union
+ |select key, value from testData
+ |""".stripMargin)
+ checkAnswer(distinctUnionDF3, testData.distinct())
+
+ val distinctUnionDF4 = sql(
+ """
+ |select distinct key, expr
+ |from
+ |(
+ | select key, key + 1 as expr
+ | from testData
+ | union all
+ | select key, key + 2 as expr
+ | from testData
+ |)
Review comment:
Manually put `CollapseProject` ahead of this rule and the project is
removed, but I don't see it is affected too. Where it produces wrong query
plan? Can you check it again?
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
