diff --git a/source/libs/executor/src/timesliceoperator.c b/source/libs/executor/src/timesliceoperator.c
index 2374d80bbf3f15430230f95177b4efe9beba2e4c..af3c44d0328812a8f7bb61557e6c1921d03512c0 100644
--- a/source/libs/executor/src/timesliceoperator.c
+++ b/source/libs/executor/src/timesliceoperator.c
@@ -96,13 +96,26 @@ static void doKeepLinearInfo(STimeSliceOperatorInfo* pSliceInfo, const SSDataBlo
     if (!pLinearInfo->isStartSet) {
       if (!colDataIsNull_s(pColInfoData, rowIndex)) {
         pLinearInfo->start.key = *(int64_t*)colDataGetData(pTsCol, rowIndex);
-        memcpy(pLinearInfo->start.val, colDataGetData(pColInfoData, rowIndex), pLinearInfo->bytes);
+        char* p = colDataGetData(pColInfoData, rowIndex);
+        if (IS_VAR_DATA_TYPE(pColInfoData->info.type)) {
+          ASSERT(varDataTLen(p) <= pColInfoData->info.bytes);
+          memcpy(pLinearInfo->start.val, p, varDataTLen(p));
+        } else {
+          memcpy(pLinearInfo->start.val, p, pLinearInfo->bytes);
+        }
       }
       pLinearInfo->isStartSet = true;
     } else if (!pLinearInfo->isEndSet) {
       if (!colDataIsNull_s(pColInfoData, rowIndex)) {
         pLinearInfo->end.key = *(int64_t*)colDataGetData(pTsCol, rowIndex);
-        memcpy(pLinearInfo->end.val, colDataGetData(pColInfoData, rowIndex), pLinearInfo->bytes);
+
+        char* p = colDataGetData(pColInfoData, rowIndex);
+        if (IS_VAR_DATA_TYPE(pColInfoData->info.type)) {
+          ASSERT(varDataTLen(p) <= pColInfoData->info.bytes);
+          memcpy(pLinearInfo->start.val, p, varDataTLen(p));
+        } else {
+          memcpy(pLinearInfo->start.val, p, pLinearInfo->bytes);
+        }
       }
       pLinearInfo->isEndSet = true;
     } else {
@@ -111,7 +124,15 @@ static void doKeepLinearInfo(STimeSliceOperatorInfo* pSliceInfo, const SSDataBlo
 
       if (!colDataIsNull_s(pColInfoData, rowIndex)) {
         pLinearInfo->end.key = *(int64_t*)colDataGetData(pTsCol, rowIndex);
-        memcpy(pLinearInfo->end.val, colDataGetData(pColInfoData, rowIndex), pLinearInfo->bytes);
+
+        char* p = colDataGetData(pColInfoData, rowIndex);
+        if (IS_VAR_DATA_TYPE(pColInfoData->info.type)) {
+          ASSERT(varDataTLen(p) <= pColInfoData->info.bytes);
+          memcpy(pLinearInfo->start.val, p, varDataTLen(p));
+        } else {
+          memcpy(pLinearInfo->start.val, p, pLinearInfo->bytes);
+        }
+
       } else {
         pLinearInfo->end.key = INT64_MIN;
       }