fix: bypass projection pruning if union set op and subquery

source/libs/parser/src/parCalcConst.c

@@ -388,6 +388,9 @@ static bool isSetUselessCol(SSetOperator* pSetOp, int32_t index, SExprNode* pPro
 }
 
 static int32_t calcConstSetOpProjections(SCalcConstContext* pCxt, SSetOperator* pSetOp, bool subquery) {
+  if (subquery && pSetOp->opType == SET_OP_TYPE_UNION) {
+    return TSDB_CODE_SUCCESS;
+  }
   int32_t index = 0;
   SNode*  pProj = NULL;
   WHERE_EACH(pProj, pSetOp->pProjectionList) {

source/libs/planner/src/planner.c

@@ -19,6 +19,14 @@
 #include "scalar.h"
 #include "tglobal.h"
 
+static void debugPrintNode(SNode* pNode) {
+  char* pStr = NULL;
+  nodesNodeToString(pNode, false, &pStr, NULL);
+  printf("%s\n", pStr);
+  taosMemoryFree(pStr);
+  return;
+}
+
 static void dumpQueryPlan(SQueryPlan* pPlan) {
   if (!tsQueryPlannerTrace) {
     return;