fix: duplicated explain response issue

source/libs/qworker/inc/qwInt.h

@@ -127,6 +127,7 @@ typedef struct SQWTaskCtx {
   bool    queryRsped;
   bool    queryEnd;
   bool    queryContinue;
+  bool    queryExecDone;
   bool    queryInQueue;
   int32_t rspCode;
   int64_t affectedRows;  // for insert ...select stmt

source/libs/qworker/src/qworker.c

@@ -59,6 +59,8 @@ static void freeItem(void *param) {
 int32_t qwHandleTaskComplete(QW_FPARAMS_DEF, SQWTaskCtx *ctx) {
   qTaskInfo_t taskHandle = ctx->taskHandle;
 
+  ctx->queryExecDone = true;
+
   if (TASK_TYPE_TEMP == ctx->taskType && taskHandle) {
     if (ctx->explain) {
       SArray *execInfoList = taosArrayInit(4, sizeof(SExplainExecInfo));
@@ -116,6 +118,14 @@ int32_t qwExecTask(QW_FPARAMS_DEF, SQWTaskCtx *ctx, bool *queryStop) {
   DataSinkHandle sinkHandle = ctx->sinkHandle;
   SLocalFetch    localFetch = {(void *)mgmt, ctx->localExec, qWorkerProcessLocalFetch, ctx->explainRes};
 
+  if (ctx->queryExecDone) {
+    if (queryStop) {
+      *queryStop = true;
+    }
+    
+    return TSDB_CODE_SUCCESS;
+  }
+
   SArray *pResList = taosArrayInit(4, POINTER_BYTES);
   while (true) {
     QW_TASK_DLOG("start to execTask, loopIdx:%d", i++);