diff --git a/src/client/src/tscParseInsert.c b/src/client/src/tscParseInsert.c
index 17f9f27abcb4c6f30171f8349c3afbd9e0f3e158..f17afa0f780f14f2ec6a140b01858677803f2969 100644
--- a/src/client/src/tscParseInsert.c
+++ b/src/client/src/tscParseInsert.c
@@ -1345,12 +1345,15 @@ int tsParseSql(SSqlObj *pSql, bool initial) {
     }
 
     // make a backup as tsParseInsertSql may modify the string
-//    char* sqlstr = strdup(pSql->sqlstr);
+    char* sqlstr = strdup(pSql->sqlstr);
     ret = tsParseInsertSql(pSql);
-    if (/*(sqlstr == NULL) || */(pSql->parseRetry >= 1) ||
+    if ((sqlstr == NULL) || (pSql->parseRetry >= 1) ||
         (ret != TSDB_CODE_TSC_SQL_SYNTAX_ERROR && ret != TSDB_CODE_TSC_INVALID_SQL)) {
+      free(sqlstr);
     } else {
       tscResetSqlCmd(pCmd, true);
+      free(pSql->sqlstr);
+      pSql->sqlstr = sqlstr;
       pSql->parseRetry++;
       if ((ret = tsInsertInitialCheck(pSql)) == TSDB_CODE_SUCCESS) {
         ret = tsParseInsertSql(pSql);