故障原因:开发人员在主库上修改了一张表的结构,加了一个字段,从库由于各种原因没有同步过去,导致主从同步失败。故障处理:1、查看在从库上查看同步状态:mys
故障原因:
开发人员在主库上修改了一张表的结构,加了一个字段,,从库由于各种原因没有同步过去,导致主从同步失败。
故障处理:
1、查看在从库上查看同步状态:
2、从上面可以看出表act_id的js_code字段在从库上没有,可以对比一下主库和从库这张表的结构:
查看主库:
查看从库:
mysql> desc act_id; +-----------------+------------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-----------------+------------------+------+-----+---------+----------------+ | act_id | int(10) unsigned | NO | PRI | NULL | auto_increment | | name | varchar(512) | NO | | NULL | | | fields | varchar(512) | NO | | NULL | | | remark | varchar(512) | NO | | NULL | | | create_user | varchar(256) | NO | | NULL | | | duty_user_name | varchar(256) | NO | | NULL | | | duty_user_email | varchar(256) | YES | | NULL | | | duty_user_phone | varchar(256) | YES | | NULL | | | create_time | bigint(20) | NO | | NULL | | | update_time | bigint(20) | NO | | NULL | | +-----------------+------------------+------+-----+---------+----------------+ 10 rows in set (0.00 sec)3、在正式处理故障之前要停掉主库和从库的slave进程(我的环境是做了双向同步,即主主同步)
mysql> slave stop; Query OK, 0 rows affected (0.12 sec)4、在从库上加缺少的字段:
alter table act_id add js_code text not Null AFTER fields;5、启动从库的slave进程,查看主从状态:
mysql> slave start; Query OK, 0 rows affected (0.00 sec) mysql> show slave status\G *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 10.10.100.100 Master_User: slave Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000009 Read_Master_Log_Pos: 917648 Relay_Log_File: mysqld-relay-bin.000117 Relay_Log_Pos: 253 Relay_Master_Log_File: mysql-bin.000009 Slave_IO_Running: Yes Slave_SQL_Running: Yes Replicate_Do_DB: Replicate_Ignore_DB: mysql,information_schema,performance_schema,test,mysql,information_schema,performance_schema,test Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0 Last_Error: Skip_Counter: 0 Exec_Master_Log_Pos: 917648 Relay_Log_Space: 556 Until_Condition: None Until_Log_File: Until_Log_Pos: 0 Master_SSL_Allowed: No Master_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: 0 Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 1 1 row in set (0.00 sec)
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