check table & repair table

mysql> check table mysql.proxies_priv;
+--------------------+-------+----------+-------------------------------------------------------------------------------------------+
| Table              | Op    | Msg_type | Msg_text                                                                                  |
+--------------------+-------+----------+-------------------------------------------------------------------------------------------+
| mysql.proxies_priv | check | error    | Table upgrade required. Please do "REPAIR TABLE `proxies_priv`" or dump/reload to fix it! |
+--------------------+-------+----------+-------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

mysql> repair table mysql.proxies_priv;
+--------------------+--------+----------+-------------------------------------------------------------------------------------+
| Table              | Op     | Msg_type | Msg_text                                                                            |
+--------------------+--------+----------+-------------------------------------------------------------------------------------+
| mysql.proxies_priv | repair | Note     | TIME/TIMESTAMP/DATETIME columns of old format have been upgraded to the new format. |
| mysql.proxies_priv | repair | status   | OK                                                                                  |
+--------------------+--------+----------+-------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)

mysql> check table mysql.proxies_priv;
+--------------------+-------+----------+----------+
| Table              | Op    | Msg_type | Msg_text |
+--------------------+-------+----------+----------+
| mysql.proxies_priv | check | status   | OK       |
+--------------------+-------+----------+----------+
1 row in set (0.00 sec)