sql: fix checkScanParallelizationIfLocal for groupNode

This commit fixes a bug in `checkScanParallelizationIfLocal` that caused
it to ignore all but the last aggregate function in a `groupNode`. This
has been fixed and a test has been added. In addition, an early return
has been added to the `renderNode` case.

Release note: None

Author: mgartner

pkg/sql/distsql_physical_planner.go

@@ -5322,16 +5322,22 @@ func checkScanParallelizationIfLocal(
 			return
 		case *groupNode:
 			for _, f := range n.funcs {
-				prohibitParallelization = f.hasFilter()
+				if f.hasFilter() {
+					prohibitParallelization = true
+					// Do not recurse.
+					return
+				}
 			}
 		case *joinNode:
 			prohibitParallelization = n.pred.onCond != nil
 		case *renderNode:
-			// Only support projections since render expressions might be handled
-			// via a wrapped row-by-row processor.
+			// Only support projections since render expressions might be
+			// handled via a wrapped row-by-row processor.
 			for _, e := range n.render {
 				if _, isIVar := e.(*tree.IndexedVar); !isIVar {
 					prohibitParallelization = true
+					// Do not recurse.
+					return
 				}
 			}
 		case *scanNode:

pkg/sql/distsql_physical_planner_test.go

@@ -1994,6 +1994,17 @@ func TestCheckScanParallelizationIfLocal(t *testing.T) {
 			// Filtering aggregation is not natively supported.
 			prohibitParallelization: true,
 		},
+		{
+			plan: planComponents{main: planMaybePhysical{planNode: &groupNode{
+				singleInputPlanNode: singleInputPlanNode{scanToParallelize},
+				funcs: []*aggregateFuncHolder{
+					{filterRenderIdx: 0},
+					{filterRenderIdx: tree.NoColumnIdx},
+				}},
+			}},
+			// Filtering aggregation is not natively supported.
+			prohibitParallelization: true,
+		},
 		{
 			plan: planComponents{main: planMaybePhysical{planNode: &indexJoinNode{
 				singleInputPlanNode: singleInputPlanNode{scanToParallelize},
@@ -2028,6 +2039,16 @@ func TestCheckScanParallelizationIfLocal(t *testing.T) {
 			// prohibit the parallelization for all non-IndexedVar expressions).
 			prohibitParallelization: true,
 		},
+		{
+			plan: planComponents{main: planMaybePhysical{planNode: &renderNode{
+				singleInputPlanNode: singleInputPlanNode{scanToParallelize},
+				render:              []tree.TypedExpr{&tree.IndexedVar{Idx: 0}, &tree.IsNullExpr{}},
+			}}},
+			// Not a simple projection (some expressions might be handled by
+			// wrapping a row-execution processor, so we choose to be safe and
+			// prohibit the parallelization for all non-IndexedVar expressions).
+			prohibitParallelization: true,
+		},
 		{
 			plan:                     planComponents{main: planMaybePhysical{planNode: &sortNode{singleInputPlanNode: singleInputPlanNode{scanToParallelize}}}},
 			hasScanNodeToParallelize: true,