fix: fix null bytes issue

source/common/src/tdatablock.c

@@ -320,7 +320,9 @@ int32_t colDataAssign(SColumnInfoData* pColumnInfoData, const SColumnInfoData* p
     memcpy(pColumnInfoData->pData, pSource->pData, pSource->varmeta.length);
   } else {
     memcpy(pColumnInfoData->nullbitmap, pSource->nullbitmap, BitmapLen(numOfRows));
-    memcpy(pColumnInfoData->pData, pSource->pData, pSource->info.bytes * numOfRows);
+    if (pSource->pData) {
+      memcpy(pColumnInfoData->pData, pSource->pData, pSource->info.bytes * numOfRows);
+    }
   }
 
   pColumnInfoData->hasNull = pSource->hasNull;

source/libs/scalar/src/scalar.c

@@ -729,6 +729,7 @@ EDealRes sclRewriteFunction(SNode** pNode, SScalarCtx *ctx) {
 
   if (colDataIsNull_s(output.columnData, 0)) {
     res->node.resType.type = TSDB_DATA_TYPE_NULL;
+    res->node.resType.bytes = tDataTypes[TSDB_DATA_TYPE_NULL].bytes;    
   } else {
     res->node.resType.type = output.columnData->info.type;
     res->node.resType.bytes = output.columnData->info.bytes;
@@ -819,6 +820,7 @@ EDealRes sclRewriteOperator(SNode** pNode, SScalarCtx *ctx) {
   if (colDataIsNull_s(output.columnData, 0)) {
     if(node->node.resType.type != TSDB_DATA_TYPE_JSON){
       res->node.resType.type = TSDB_DATA_TYPE_NULL;
+      res->node.resType.bytes = tDataTypes[TSDB_DATA_TYPE_NULL].bytes;
     }else{
       res->node.resType = node->node.resType;
       res->isNull = true;

tests/script/tsim/query/scalarNull.sim

@@ -89,5 +89,10 @@ endi
 #TODO: MOVE IT TO NORMAL CASE
 sql_error select * from tb1 where not (null);
 
+sql select sum(1/0) from tb1;
+if $rows != 1 then
+  return -1
+endi
+
 
 system sh/exec.sh -n dnode1 -s stop -x SIGINT