MySQL误删数据后快速恢复的方法

传统解法

用全量备份重搭实例，再利用增量binlog备份，恢复到误操作之前的状态。然后跳过误操作的SQL，再继续应用binlog。

利用binlog2sql快速闪回

首先，确认你的MySQL server开启了binlog，设置了以下参数:

[mysqld]

server-id = 1

log_bin = /var/log/mysql/mysql-bin.log

max_binlog_size = 100M

binlog-format = row

如果没有开启binlog，也没有预先生成回滚SQL，那真的无法快速回滚了。对存放重要业务数据的MySQL，强烈建议开启binlog。

随后，安装开源工具binlog2sql。binlog2sql是一款简单易用的binlog解析工具，其中一个功能就是生成回滚SQL。

shell> git clone https://github.com/danfengcao/binlog2sql.git

shell> pip install -r requirements.txt

然后，我们就可以生成回滚SQL了。

背景：小明在20点多时误删了test库tbl表整张表的数据，需要紧急回滚。

test库tbl表原有数据
mysql> select * from tbl;
+----	+--------	+---------------------	+
\| id \| name \| addtime			\|
+----	+--------	+---------------------	+

| 1 | 小赵 | 2016-12-10 00:04:33 |

| 2 | 小钱 | 2016-12-10 00:04:48 |

| 3 | 小孙 | 2016-12-13 20:25:00 |

| 4 | 小李 | 2016-12-12 00:00:00 |

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

4 rows in set (0.00 sec)

mysql> delete from tbl;

Query OK, 4 rows affected (0.00 sec)

20:28时，tbl表误操作被清空

mysql> select * from tbl;

Empty set (0.00 sec)

恢复数据步骤：

1、登录mysql，查看目前的binlog文件

mysql> show master status;

+------------------	+-----------	+
\| Log_name	\| File_size \|
+------------------	+-----------	+
\| mysql-bin.000051 \|		967 \|
\| mysql-bin.000052 \|		965 \|
+------------------	+-----------	+

2、最新的binlog文件是mysql-bin.000052，我们再定位误操作SQL的binlog位置。误操作人只能知道大致的误操作时间，我们根据大致时间过滤数据。

shell> python binlog2sql/binlog2sql.py -h127.0.0.1 -P3306 -uadmin -p'admin' -dtest -ttbl --start-file='mysql-bin.000052' --start-datetime='2016-12-13 20:25:00' --stop-datetime='2016-12-13 20:30:00' 输出：

INSERT INTO `test`.`tbl`(`addtime`, `id`, `name`) VALUES ('2016-12-13 20:25:00', 3, '小孙'); #start 4 end 290 time 2016-12-13 20:25:46 INSERT INTO `test`.`tbl`(`addtime`, `id`, `name`) VALUES ('2016-12-13 20:26:00', 4, '小李'); #start 317 end 487 time 2016-12-13 20:26:26

UPDATE `test`.`tbl` SET `addtime`='2016-12-12 00:00:00', `id`=4, `name`='小李' WHERE `addtime`='2016-12-13 20:26:00' AND `id`=4 AND `name`='小李' LIMIT 1; #start 514 end 701 time 2016-12-13 20:27:07

DELETE FROM `test`.`tbl` WHERE `addtime`='2016-12-10 00:04:33' AND `id`=1 AND `name`='小赵' LIMIT 1; #start 728 end 938 time 2016-12-13 20:28:05

DELETE FROM `test`.`tbl` WHERE `addtime`='2016-12-10 00:04:48' AND `id`=2 AND `name`='小钱' LIMIT 1; #start 728 end 938 time 2016-12-13 20:28:05

DELETE FROM `test`.`tbl` WHERE `addtime`='2016-12-13 20:25:00' AND `id`=3 AND `name`='小孙' LIMIT 1; #start 728 end 938 time 2016-12-13 20:28:05

DELETE FROM `test`.`tbl` WHERE `addtime`='2016-12-12 00:00:00' AND `id`=4 AND `name`='小李' LIMIT 1; #start 728 end 938 time 2016-12-13 20:28:05

3、我们得到了误操作sql的准确位置在728-938之间，再根据位置进一步过滤，使用flashback模式生成回滚sql，检查回滚sql是否正确

shell> python binlog2sql/binlog2sql.py -h127.0.0.1 -P3306 -uadmin -p'admin' -dtest -ttbl --start-file='mysql-bin.000052' --start-pos=3346 --end-pos=3556 -B 输出：

INSERT INTO `test`.`tbl`(`addtime`, `id`, `name`) VALUES ('2016-12-12 00:00:00', 4, '小李'); #start 728 end 938 time 2016-12-13 20:28:05

INSERT INTO `test`.`tbl`(`addtime`, `id`, `name`) VALUES ('2016-12-13 20:25:00', 3, '小孙'); #start 728 end 938 time 2016-12-13 20:28:05

INSERT INTO `test`.`tbl`(`addtime`, `id`, `name`) VALUES ('2016-12-10 00:04:48', 2, '小钱'); #start 728 end 938 time 2016-12-13 20:28:05

INSERT INTO `test`.`tbl`(`addtime`, `id`, `name`) VALUES ('2016-12-10 00:04:33', 1, '小赵'); #start 728 end 938 time 2016-12-13 20:28:05

确认回滚sql正确，执行回滚语句。登录mysql确认，数据回滚成功。

shell> python binlog2sql.py -h127.0.0.1 -P3306 -uadmin -p'admin' -dtest -ttbl --start-file='mysql-bin.000052' --start-pos=3346 --end-pos=3556 -B | mysql -h127.0.0.1 -P3306 -uadmin -p'admin'

mysql> select * from tbl;
+----	+--------	+---------------------	+
\| id \| name		\| addtime	\|
+----	+--------	+---------------------	+