Merge pull request #2608 from taosdata/bugfix/stream

fix invalid read in CQ

src/cq/src/cqMain.c

@@ -269,8 +269,14 @@ static void cqProcessStreamRes(void *param, TAOS_RES *tres, TAOS_ROW row) {
     void* val = row[i];
     if (val == NULL) {
       val = getNullValue(c->type);
-    } else if (IS_VAR_DATA_TYPE(c->type)) {
+    } else if (c->type == TSDB_DATA_TYPE_BINARY) {
       val = ((char*)val) - sizeof(VarDataLenT);
+    } else if (c->type == TSDB_DATA_TYPE_NCHAR) {
+      char buf[TSDB_MAX_NCHAR_LEN];
+      size_t len = taos_fetch_lengths(tres)[i];
+      taosMbsToUcs4(val, len, buf, sizeof(buf), &len);
+      memcpy(val + sizeof(VarDataLenT), buf, len);
+      varDataLen(val) = len;
     }
     tdAppendColVal(trow, val, c->type, c->bytes, c->offset);
   }