mysql在SBR下恢复误删除的表

(system@localhost) [zeng]> select * from t;

+------+--------------------------+----------------------------------+

| id | context | hash_value |

+------+--------------------------+----------------------------------+

| 1 | beijingbeijing | 09746eef633dbbccb7997dfd795cff17 |

| 2 | beijingbeijing | 09746eef633dbbccb7997dfd795cff17 |

| 3 | beijingbeijing | 09746eef633dbbccb7997dfd795cff17 |

| 4 | beijing 2008beijing 2008 | 1c0ddb82cca9ed63e1cacbddd3f74082 |

将表备份一下：

mysqldump -usystem -psafe2016 -S /mysql/server/conf/mysql.sock zeng t >/mysql/backup/t.sql

(system@localhost) [zeng]> show master status;

+------------------+----------+--------------+------------------+-------------------+

| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |

+------------------+----------+--------------+------------------+-------------------+

| mysql-bin.000016 | 235 | | | |

+------------------+----------+--------------+------------------+-------------------+

1 row in set (0.00 sec)

(system@localhost) [zeng]> show master logs;

+------------------+-----------+

| Log_name | File_size |

+------------------+-----------+

| mysql-bin.000014 | 3253595 |

| mysql-bin.000015 | 167 |

| mysql-bin.000016 | 235 |

+------------------+-----------+

错误更新操作：

(system@localhost) [zeng]> update t set context='shanghai' where id=1;

Query OK, 1 row affected (0.02 sec)

Rows matched: 1 Changed: 1 Warnings: 0

后面又增加了记录：

(system@localhost) [zeng]> insert into t values (5,'chongqing','');

Query OK, 1 row affected (0.01 sec)

查看表的记录数：

(system@localhost) [zeng]> select * from t;

+------+--------------------------+----------------------------------+

| id | context | hash_value |

+------+--------------------------+----------------------------------+

| 1 | shanghai | 09746eef633dbbccb7997dfd795cff17 |

| 2 | beijingbeijing | 09746eef633dbbccb7997dfd795cff17 |

| 3 | beijingbeijing | 09746eef633dbbccb7997dfd795cff17 |

| 4 | beijing 2008beijing 2008 | 1c0ddb82cca9ed63e1cacbddd3f74082 |

| 5 | chongqing | |

+------+--------------------------+----------------------------------+

5 rows in set (0.00 sec)

如何恢复该表，跳过错误？

先把表备份一份：

create table t_bak as select * from t;

然后drop 表t:

drop table t;

利用前面备份的表t，用mysql命令恢复回去：

mysql -usystem -psafe2016 -S /mysql/server/conf/mysql.sock zeng </mysql/backup/t.sql

(system@localhost) [zeng]> desc t;

+------------+--------------+------+-----+---------+-------+

| Field | Type | Null | Key | Default | Extra |

+------------+--------------+------+-----+---------+-------+

| id | varchar(100) | YES | | NULL | |

| context | blob | YES | | NULL | |

| hash_value | varchar(40) | YES | | NULL | |

+------------+--------------+------+-----+---------+-------+

3 rows in set (0.00 sec)

(system@localhost) [zeng]> select * from t;

+------+--------------------------+----------------------------------+

| id | context | hash_value |

+------+--------------------------+----------------------------------+

| 1 | beijingbeijing | 09746eef633dbbccb7997dfd795cff17 |

| 2 | beijingbeijing | 09746eef633dbbccb7997dfd795cff17 |

| 3 | beijingbeijing | 09746eef633dbbccb7997dfd795cff17 |

| 4 | beijing 2008beijing 2008 | 1c0ddb82cca9ed63e1cacbddd3f74082 |

+------+--------------------------+----------------------------------+

4 rows in set (0.00 sec)

需要将更新误操作后面插入的记录恢复回去，且要跳过误操作，需要先查看binlog，确认误操作前后的时间点或位置及所有对t表操作过的命令。

(system@localhost) [zeng]> show master logs;

+------------------+-----------+

| Log_name | File_size |

+------------------+-----------+

| mysql-bin.000014 | 3253595 |

| mysql-bin.000015 | 167 |

| mysql-bin.000016 | 1929 |

+------------------+-----------+

(system@localhost) [zeng]> show master status;

+------------------+----------+--------------+------------------+-------------------+

| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |

+------------------+----------+--------------+------------------+-------------------+

| mysql-bin.000016 | 1929 | | | |

+------------------+----------+--------------+------------------+-------------------+

1 row in set (0.00 sec)

分析mysql-bin.000016确认时间点或位置：2015-08-07 16:05:46或314及操作命令。

314位置的SQL就是误操作的SQL:

# at 314

#150807 16:05:46 server id 2433306 end_log_pos 430 CRC32 0xb3ed1fbe Query thread_id=43 exec_time=0 error_code=0

use `zeng`/*!*/;

SET TIMESTAMP=1438934746/*!*/;

update t set context='shanghai' where id=1

540位置的SQL是需要重新执行的SQL:

/*!*/;

# at 540

#150807 16:07:57 server id 2433306 end_log_pos 653 CRC32 0xbf542069 Query thread_id=43 exec_time=0 error_code=0

SET TIMESTAMP=1438934877/*!*/;

insert into t values (5,'chongqing','')

/*!*/;

再执行如下：

(system@localhost) [zeng]> insert into t values (5,'chongqing','')

-> ;

Query OK, 1 row affected (0.01 sec)

再查看一下，需要的记录找回来了。

(system@localhost) [zeng]> select * from t;

+------+--------------------------+----------------------------------+

| id | context | hash_value |

+------+--------------------------+----------------------------------+

| 1 | beijingbeijing | 09746eef633dbbccb7997dfd795cff17 |

| 2 | beijingbeijing | 09746eef633dbbccb7997dfd795cff17 |

| 3 | beijingbeijing | 09746eef633dbbccb7997dfd795cff17 |

| 4 | beijing 2008beijing 2008 | 1c0ddb82cca9ed63e1cacbddd3f74082 |

| 5 | chongqing | |

+------+--------------------------+----------------------------------+

5 rows in set (0.00 sec)