diff --git a/include/common/tdatablock.h b/include/common/tdatablock.h
index 292e9a3181..fa6e4c3ae8 100644
--- a/include/common/tdatablock.h
+++ b/include/common/tdatablock.h
@@ -267,7 +267,7 @@ int32_t buildSubmitReqFromDataBlock(SSubmitReq2** pReq, const SSDataBlock* pData
 
 bool  alreadyAddGroupId(char* ctbName);
 bool  isAutoTableName(char* ctbName);
-void  buildCtbNameAddGruopId(char* ctbName, uint64_t groupId);
+void  buildCtbNameAddGroupId(char* ctbName, uint64_t groupId);
 char* buildCtbNameByGroupId(const char* stbName, uint64_t groupId);
 int32_t buildCtbNameByGroupIdImpl(const char* stbName, uint64_t groupId, char* pBuf);
 
diff --git a/source/common/src/tdatablock.c b/source/common/src/tdatablock.c
index 9a39812bc9..9f55b67ea3 100644
--- a/source/common/src/tdatablock.c
+++ b/source/common/src/tdatablock.c
@@ -2118,28 +2118,28 @@ _end:
   return TSDB_CODE_SUCCESS;
 }
 
-void  buildCtbNameAddGruopId(char* ctbName, uint64_t groupId){
+void  buildCtbNameAddGroupId(char* ctbName, uint64_t groupId){
   char tmp[TSDB_TABLE_NAME_LEN] = {0};
   snprintf(tmp, TSDB_TABLE_NAME_LEN, "_%"PRIu64, groupId);
   ctbName[TSDB_TABLE_NAME_LEN - strlen(tmp) - 1] = 0;  // put groupId to the end
   strcat(ctbName, tmp);
 }
 
-bool  isAutoTableName(char* ctbName){
-  return (strlen(ctbName) == 34 && ctbName[0] == 't' && ctbName[1] == '_');
-}
+// auto stream subtable name starts with 't_', followed by the first segment of MD5 digest for group vals.
+// the total length is fixed to be 34 bytes.
+bool isAutoTableName(char* ctbName) { return (strlen(ctbName) == 34 && ctbName[0] == 't' && ctbName[1] == '_'); }
 
-bool  alreadyAddGroupId(char* ctbName){
+bool alreadyAddGroupId(char* ctbName) {
   size_t len = strlen(ctbName);
   size_t _location = len - 1;
-  while(_location > 0){
-    if(ctbName[_location] < '0' || ctbName[_location] > '9'){
+  while (_location > 0) {
+    if (ctbName[_location] < '0' || ctbName[_location] > '9') {
       break;
     }
     _location--;
   }
 
-  return ctbName[_location] == '_' &&  len - 1 - _location > 15;  //15 means the min length of groupid
+  return ctbName[_location] == '_' && len - 1 - _location >= 15;  // 15 means the min length of groupid
 }
 
 char* buildCtbNameByGroupId(const char* stbFullName, uint64_t groupId) {
diff --git a/source/dnode/vnode/src/tq/tqSink.c b/source/dnode/vnode/src/tq/tqSink.c
index 42bd1bc59c..9ff4e3ba62 100644
--- a/source/dnode/vnode/src/tq/tqSink.c
+++ b/source/dnode/vnode/src/tq/tqSink.c
@@ -72,7 +72,7 @@ int32_t tqBuildDeleteReq(STQ* pTq, const char* stbFullName, const SSDataBlock* p
       name = taosMemoryCalloc(1, TSDB_TABLE_NAME_LEN);
       memcpy(name, varDataVal(varTbName), varDataLen(varTbName));
       if (newSubTableRule && !isAutoTableName(name) && !alreadyAddGroupId(name) && groupId != 0) {
-        buildCtbNameAddGruopId(name, groupId);
+        buildCtbNameAddGroupId(name, groupId);
       }
     } else if (stbFullName) {
       name = buildCtbNameByGroupId(stbFullName, groupId);
@@ -185,23 +185,26 @@ void setCreateTableMsgTableName(SVCreateTbReq* pCreateTableReq, SSDataBlock* pDa
         !alreadyAddGroupId(pDataBlock->info.parTbName) && gid != 0) {
       pCreateTableReq->name = taosMemoryCalloc(1, TSDB_TABLE_NAME_LEN);
       strcpy(pCreateTableReq->name, pDataBlock->info.parTbName);
-      buildCtbNameAddGruopId(pCreateTableReq->name, gid);
+      buildCtbNameAddGroupId(pCreateTableReq->name, gid);
+//      tqDebug("gen name from:%s", pDataBlock->info.parTbName);
     } else {
       pCreateTableReq->name = taosStrdup(pDataBlock->info.parTbName);
+//      tqDebug("copy name:%s", pDataBlock->info.parTbName);
     }
   } else {
     pCreateTableReq->name = buildCtbNameByGroupId(stbFullName, gid);
+//    tqDebug("gen name from stbFullName:%s gid:%"PRId64, stbFullName, gid);
   }
 }
 
 static int32_t doBuildAndSendCreateTableMsg(SVnode* pVnode, char* stbFullName, SSDataBlock* pDataBlock,
                                             SStreamTask* pTask, int64_t suid) {
-  tqDebug("s-task:%s build create table msg", pTask->id.idStr);
-
   STSchema* pTSchema = pTask->outputInfo.tbSink.pTSchema;
   int32_t   rows = pDataBlock->info.rows;
   SArray*   tagArray = taosArrayInit(4, sizeof(STagVal));
-  ;
+
+  tqDebug("s-task:%s build create %d table(s) msg", pTask->id.idStr, rows);
+
   int32_t code = 0;
 
   SVCreateTbBatchReq reqs = {0};
@@ -670,7 +673,8 @@ int32_t setDstTableDataUid(SVnode* pVnode, SStreamTask* pTask, SSDataBlock* pDat
     } else {
       if (pTask->ver >= SSTREAM_TASK_SUBTABLE_CHANGED_VER && pTask->subtableWithoutMd5 != 1 &&
           !isAutoTableName(dstTableName) && !alreadyAddGroupId(dstTableName) && groupId != 0) {
-        buildCtbNameAddGruopId(dstTableName, groupId);
+        tqDebug("s-task:%s append groupId:%" PRId64 " for generated dstTable:%s", id, groupId, dstTableName);
+        buildCtbNameAddGroupId(dstTableName, groupId);
       }
     }
 
diff --git a/source/libs/stream/src/streamDispatch.c b/source/libs/stream/src/streamDispatch.c
index 9383383dc0..60c545b9e5 100644
--- a/source/libs/stream/src/streamDispatch.c
+++ b/source/libs/stream/src/streamDispatch.c
@@ -575,7 +575,7 @@ int32_t streamSearchAndAddBlock(SStreamTask* pTask, SStreamDispatchReq* pReqs, S
           !isAutoTableName(pDataBlock->info.parTbName) &&
           !alreadyAddGroupId(pDataBlock->info.parTbName) &&
           groupId != 0){
-        buildCtbNameAddGruopId(pDataBlock->info.parTbName, groupId);
+        buildCtbNameAddGroupId(pDataBlock->info.parTbName, groupId);
       }
     } else {
       buildCtbNameByGroupIdImpl(pTask->outputInfo.shuffleDispatcher.stbFullName, groupId, pDataBlock->info.parTbName);