Merge cockroachdb#57524

57524: opt: fix bug in ExtractJoinEqualities rule r=RaduBerinde a=RaduBerinde If the join is semi/anti, this rule generates an incorrect projection (which passes through columns not in input). Similar to cockroachdb#57501. Other normalization rules prune the columns so this doesn't lead to a bad outcome (at least in most cases). I will add an assertion in CheckExpr for this condition in a separate PR - without this fix, the assertion fires on an existing test. Release note: None Co-authored-by: Radu Berinde <[email protected]>
knz · Dec 4, 2020 · aa69b42 · aa69b42
2 parents 3c740d0 + 7614e3f
commit aa69b42
Showing 1 changed file with 7 additions and 1 deletion.
diff --git a/pkg/sql/opt/norm/join_funcs.go b/pkg/sql/opt/norm/join_funcs.go
@@ -553,7 +553,13 @@ func (c *CustomFuncs) ExtractJoinEquality(
 	)
 
 	// Project away the synthesized columns.
-	return c.f.ConstructProject(join, memo.EmptyProjectionsExpr, leftCols.Union(rightCols))
+	outputCols := leftCols
+	if joinOp != opt.SemiJoinOp && joinOp != opt.AntiJoinOp {
+		// Semi/Anti join only produce the left side columns. All other join types
+		// produce columns from both sides.
+		outputCols = leftCols.Union(rightCols)
+	}
+	return c.f.ConstructProject(join, memo.EmptyProjectionsExpr, outputCols)
 }
 
 // CommuteJoinFlags returns a join private for the commuted join (where the left