restore sclRewriteOperator logic

source/libs/scalar/src/scalar.c

@@ -824,10 +824,14 @@ EDealRes sclRewriteOperator(SNode** pNode, SScalarCtx *ctx) {
 
   res->translate = true;
 
-  res->node.resType = node->node.resType;
   if (colDataIsNull_s(output.columnData, 0)) {
-    res->isNull = true;
-    res->node.resType = node->node.resType;
+    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->isNull = true;
+      res->node.resType = node->node.resType;
+    }
   } else {
     int32_t type = output.columnData->info.type;
     if (IS_VAR_DATA_TYPE(type)) {  // todo refactor