ERROR 1682 (HY000): Native table 'performance_schema'.'threads' has the wrong structure

MySQL  从5.5.20 升级到5.6.21 启动后报如下错误：

[ERROR] Column count of mysql.threads is wrong. Expected 14, found 3. Created with MySQL 50520, now running 50621. Please use mysql_upgrade to fix this error.

注意这里是报的错是mysql库中的threads 表，实际上mysql库中是没有这张表的。这张表存在于performance_schema中。

 

当去访问performance_schema中的threads表时，又出如下错误。
ERROR 1682 (HY000): Native table 'performance_schema'.'threads' has the wrong structure

mysql> select version();
+-------------------------------------------+
| version()                                 |
+-------------------------------------------+
| 5.6.21-enterprise-commercial-advanced-log |
+-------------------------------------------+
1 row in set (0.00 sec)

mysql> use performance_schema
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

mysql> select * from     threads;         
ERROR 1682 (HY000): Native table 'performance_schema'.'threads' has the wrong structure

 

原因在于升级的时候，这张表没升成功。

 

删除threads表，重建theads表，重启MySql，问题解决。

mysql> drop table    threads;
Query OK, 0 rows affected (0.00 sec)

 

mysql> CREATE TABLE `threads` (
    ->   `THREAD_ID` bigint(20) unsigned NOT NULL,
    ->   `NAME` varchar(128) NOT NULL,
    ->   `TYPE` varchar(10) NOT NULL,
    ->   `PROCESSLIST_ID` bigint(20) unsigned DEFAULT NULL,
    ->   `PROCESSLIST_USER` varchar(16) DEFAULT NULL,
    ->   `PROCESSLIST_HOST` varchar(60) DEFAULT NULL,
    ->   `PROCESSLIST_DB` varchar(64) DEFAULT NULL,
    ->   `PROCESSLIST_COMMAND` varchar(16) DEFAULT NULL,
    ->   `PROCESSLIST_TIME` bigint(20) DEFAULT NULL,
    ->   `PROCESSLIST_STATE` varchar(64) DEFAULT NULL,
    ->   `PROCESSLIST_INFO` longtext,
    ->   `PARENT_THREAD_ID` bigint(20) unsigned DEFAULT NULL,
    ->   `ROLE` varchar(64) DEFAULT NULL,
    ->   `INSTRUMENTED` enum('YES','NO') NOT NULL
    -> ) ENGINE=PERFORMANCE_SCHEMA DEFAULT CHARSET=utf8;
Query OK, 0 rows affected (0.00 sec)