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[SPARK-41162][SQL][3.3] Fix anti- and semi-join for self-join with ag…
…gregations ### What changes were proposed in this pull request? Backport apache#39131 to branch-3.3. Rule `PushDownLeftSemiAntiJoin` should not push an anti-join below an `Aggregate` when the join condition references an attribute that exists in its right plan and its left plan's child. This usually happens when the anti-join / semi-join is a self-join while `DeduplicateRelations` cannot deduplicate those attributes (in this example due to the projection of `value` to `id`). This behaviour already exists for `Project` and `Union`, but `Aggregate` lacks this safety guard. ### Why are the changes needed? Without this change, the optimizer creates an incorrect plan. This example fails with `distinct()` (an aggregation), and succeeds without `distinct()`, but both queries are identical: ```scala val ids = Seq(1, 2, 3).toDF("id").distinct() val result = ids.withColumn("id", $"id" + 1).join(ids, Seq("id"), "left_anti").collect() assert(result.length == 1) ``` With `distinct()`, rule `PushDownLeftSemiAntiJoin` creates a join condition `(value#907 + 1) = value#907`, which can never be true. This effectively removes the anti-join. **Before this PR:** The anti-join is fully removed from the plan. ``` == Physical Plan == AdaptiveSparkPlan (16) +- == Final Plan == LocalTableScan (1) (16) AdaptiveSparkPlan Output [1]: [id#900] Arguments: isFinalPlan=true ``` This is caused by `PushDownLeftSemiAntiJoin` adding join condition `(value#907 + 1) = value#907`, which is wrong as because `id#910` in `(id#910 + 1) AS id#912` exists in the right child of the join as well as in the left grandchild: ``` === Applying Rule org.apache.spark.sql.catalyst.optimizer.PushDownLeftSemiAntiJoin === !Join LeftAnti, (id#912 = id#910) Aggregate [id#910], [(id#910 + 1) AS id#912] !:- Aggregate [id#910], [(id#910 + 1) AS id#912] +- Project [value#907 AS id#910] !: +- Project [value#907 AS id#910] +- Join LeftAnti, ((value#907 + 1) = value#907) !: +- LocalRelation [value#907] :- LocalRelation [value#907] !+- Aggregate [id#910], [id#910] +- Aggregate [id#910], [id#910] ! +- Project [value#914 AS id#910] +- Project [value#914 AS id#910] ! +- LocalRelation [value#914] +- LocalRelation [value#914] ``` The right child of the join and in the left grandchild would become the children of the pushed-down join, which creates an invalid join condition. **After this PR:** Join condition `(id#910 + 1) AS id#912` is understood to become ambiguous as both sides of the prospect join contain `id#910`. Hence, the join is not pushed down. The rule is then not applied any more. The final plan contains the anti-join: ``` == Physical Plan == AdaptiveSparkPlan (24) +- == Final Plan == * BroadcastHashJoin LeftSemi BuildRight (14) :- * HashAggregate (7) : +- AQEShuffleRead (6) : +- ShuffleQueryStage (5), Statistics(sizeInBytes=48.0 B, rowCount=3) : +- Exchange (4) : +- * HashAggregate (3) : +- * Project (2) : +- * LocalTableScan (1) +- BroadcastQueryStage (13), Statistics(sizeInBytes=1024.0 KiB, rowCount=3) +- BroadcastExchange (12) +- * HashAggregate (11) +- AQEShuffleRead (10) +- ShuffleQueryStage (9), Statistics(sizeInBytes=48.0 B, rowCount=3) +- ReusedExchange (8) (8) ReusedExchange [Reuses operator id: 4] Output [1]: [id#898] (24) AdaptiveSparkPlan Output [1]: [id#900] Arguments: isFinalPlan=true ``` ### Does this PR introduce _any_ user-facing change? It fixes correctness. ### How was this patch tested? Unit tests in `DataFrameJoinSuite` and `LeftSemiAntiJoinPushDownSuite`. Closes apache#39409 from EnricoMi/branch-antijoin-selfjoin-fix-3.3. Authored-by: Enrico Minack <github@enrico.minack.dev> Signed-off-by: Wenchen Fan <wenchen@databricks.com>
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