diff --git a/src/inc/taosdef.h b/src/inc/taosdef.h
index 1e0ddf0f9f..251e3a9e40 100644
--- a/src/inc/taosdef.h
+++ b/src/inc/taosdef.h
@@ -206,7 +206,7 @@ void tsDataSwap(void *pLeft, void *pRight, int32_t type, int32_t size);
 #define TSDB_MAX_SAVED_SQL_LEN    TSDB_MAX_COLUMNS * 64
 #define TSDB_MAX_SQL_LEN          TSDB_PAYLOAD_SIZE
 #define TSDB_MAX_SQL_SHOW_LEN     256
-#define TSDB_MAX_ALLOWED_SQL_LEN  (8*1024*1024U)          // sql length should be less than 6mb
+#define TSDB_MAX_ALLOWED_SQL_LEN  (8*1024*1024U)          // sql length should be less than 8mb
 
 #define TSDB_MAX_BYTES_PER_ROW    TSDB_MAX_COLUMNS * 64
 #define TSDB_MAX_TAGS_LEN         65536