diff --git a/src/inc/taosdef.h b/src/inc/taosdef.h
index 20c7af6a21d9a385d00fb3e52fe2a6ffd3d0729e..ec1e1fc330c8713b0f1135ad19887e56ff99ae8f 100644
--- a/src/inc/taosdef.h
+++ b/src/inc/taosdef.h
@@ -257,7 +257,7 @@ void tsDataSwap(void *pLeft, void *pRight, int32_t type, int32_t size, void* buf
 #define TSDB_MAX_SAVED_SQL_LEN    TSDB_MAX_COLUMNS * 64
 #define TSDB_MAX_SQL_LEN          TSDB_PAYLOAD_SIZE
 #define TSDB_MAX_SQL_SHOW_LEN     512
-#define TSDB_MAX_ALLOWED_SQL_LEN  (8*1024*1024U)          // sql length should be less than 8mb
+#define TSDB_MAX_ALLOWED_SQL_LEN  (1*1024*1024U)          // sql length should be less than 1mb
 
 #define TSDB_APPNAME_LEN          TSDB_UNI_LEN