Itu hanya kosong untuk Anda karena Anda belum mengatur sql_mode. Jika Anda menyetelnya, kueri itu akan menunjukkan detailnya kepada Anda:
mysql> SELECT @@sql_mode;
+------------+
| @@sql_mode |
+------------+
| |
+------------+
1 row in set (0.00 sec)
mysql> set sql_mode=ORACLE;
Query OK, 0 rows affected (0.00 sec)
mysql> SELECT @@sql_mode;
+----------------------------------------------------------------------------------------------------------------------+
| @@sql_mode |
+----------------------------------------------------------------------------------------------------------------------+
| PIPES_AS_CONCAT,ANSI_QUOTES,IGNORE_SPACE,ORACLE,NO_KEY_OPTIONS,NO_TABLE_OPTIONS,NO_FIELD_OPTIONS,NO_AUTO_CREATE_USER |
+----------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)