diff --git a/src/client/inc/tscUtil.h b/src/client/inc/tscUtil.h
index 2c4d711520471cb3c1cc6acc308479593a24c0f6..a9ac788bc3065f7230e10f1c58273ef90f70c6fb 100644
--- a/src/client/inc/tscUtil.h
+++ b/src/client/inc/tscUtil.h
@@ -123,7 +123,6 @@ int32_t tscGetDataBlockFromList(SHashObj* pHashList, int64_t id, int32_t size, i
  */
 bool tscIsPointInterpQuery(SQueryInfo* pQueryInfo);
 bool tscIsTWAQuery(SQueryInfo* pQueryInfo);
-bool tscIsDiffQuery(SQueryInfo* pQueryInfo);
 bool tscIsSessionWindowQuery(SQueryInfo* pQueryInfo);
 bool tscIsSecondStageQuery(SQueryInfo* pQueryInfo);
 bool tsIsArithmeticQueryOnAggResult(SQueryInfo* pQueryInfo);
diff --git a/src/client/src/tscSQLParser.c b/src/client/src/tscSQLParser.c
index 1503638a03c167ba64239187969180a0fb56092c..d91301adfec4261a4971fdd584b4b3892574d2cd 100644
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -3072,7 +3072,7 @@ bool hasUnsupportFunctionsForSTableQuery(SSqlCmd* pCmd, SQueryInfo* pQueryInfo)
     }
   }
 
-  if (tscIsTWAQuery(pQueryInfo) || tscIsDiffQuery(pQueryInfo)) {
+  if (tscIsTWAQuery(pQueryInfo) || tscIsDiffDerivQuery(pQueryInfo)) {
     if (pQueryInfo->groupbyExpr.numOfGroupCols == 0) {
       invalidOperationMsg(tscGetErrorMsgPayload(pCmd), msg1);
       return true;
@@ -7989,7 +7989,6 @@ int32_t validateSqlNode(SSqlObj* pSql, SSqlNode* pSqlNode, SQueryInfo* pQueryInf
 
     pQueryInfo->arithmeticOnAgg   = tsIsArithmeticQueryOnAggResult(pQueryInfo);
     pQueryInfo->orderProjectQuery = tscOrderedProjectionQueryOnSTable(pQueryInfo, 0);
-//    pQueryInfo->diffQuery         = tscIsDiffQuery(pQueryInfo);
 
     SExprInfo** p = NULL;
     int32_t numOfExpr = 0;
diff --git a/src/client/src/tscUtil.c b/src/client/src/tscUtil.c
index e3dba3fcbca71f43c7be7a3c6ecbaa4a51198865..9011bae47ba78945e4f87dabb91cbb1d5d900d9e 100644
--- a/src/client/src/tscUtil.c
+++ b/src/client/src/tscUtil.c
@@ -460,24 +460,6 @@ bool tscIsTWAQuery(SQueryInfo* pQueryInfo) {
   return false;
 }
 
-bool tscIsDiffQuery(SQueryInfo* pQueryInfo) {
-  size_t num = tscNumOfExprs(pQueryInfo);
-  for(int32_t i = 0; i < num; ++i) {
-    SExprInfo* pExpr = tscExprGet(pQueryInfo, i);
-
-    int32_t f = pExpr->base.functionId;
-    if (pExpr == NULL || f == TSDB_FUNC_TS_DUMMY) {
-      continue;
-    }
-
-    if (f == TSDB_FUNC_DIFF || f == TSDB_FUNC_DERIVATIVE) {
-      return true;
-    }
-  }
-
-  return false;
-}
-
 bool tscIsSessionWindowQuery(SQueryInfo* pQueryInfo) {
   return pQueryInfo->sessionWindow.gap > 0;
 }
@@ -516,7 +498,7 @@ bool isSimpleAggregateRv(SQueryInfo* pQueryInfo) {
     return false;
   }
 
-  if (tscIsDiffQuery(pQueryInfo)) {
+  if (tscIsDiffDerivQuery(pQueryInfo)) {
     return false;
   }
 
@@ -4260,7 +4242,7 @@ int32_t tscCreateQueryFromQueryInfo(SQueryInfo* pQueryInfo, SQueryAttr* pQueryAt
   pQueryAttr->hasTagResults     = hasTagValOutput(pQueryInfo);
   pQueryAttr->stabledev         = isStabledev(pQueryInfo);
   pQueryAttr->tsCompQuery       = isTsCompQuery(pQueryInfo);
-  pQueryAttr->diffQuery         = tscIsDiffQuery(pQueryInfo);
+  pQueryAttr->diffQuery         = tscIsDiffDerivQuery(pQueryInfo);
   pQueryAttr->simpleAgg         = isSimpleAggregateRv(pQueryInfo);
   pQueryAttr->needReverseScan   = tscNeedReverseScan(pQueryInfo);
   pQueryAttr->stableQuery       = QUERY_IS_STABLE_QUERY(pQueryInfo->type);