MySQL--------基于binlog实现闪回最佳实战
1. 背景
* 为了数据安全,搭建了主从。实时主从备份只能防止硬件问题,比如主库的硬盘损坏。但对于误操作,则无能为力。比如在主库误删一张表,或者一个update语句没有指定where条件,导致全表被更新。当操作被同步到从库上后,则主从都“回天无力”。
* 闪回用于快速恢复由于误操作丢失的数据。在DBA误操作时,可以把数据库恢复到以前某个时间点(或者说某个binlog的某个pos)。比如忘了带where条件的update、delete操作,传统的恢复方式是利用全备+二进制日志前滚进行恢复,相比于传统的全备+增备,flashback显然更为快速、简单。
2. 测试环境
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mysql> show variables like 'version' ;
+ ---------------+------------+
| Variable_name | Value | + ---------------+------------+
| version | 5.6.36-log | + ---------------+------------+
1 row in set (0.03 sec)
mysql> show variables like 'datadir' ;
+ ---------------+--------------------+
| Variable_name | Value | + ---------------+--------------------+
| datadir | /data/mysql_data6/ | + ---------------+--------------------+
1 row in set (0.00 sec)
mysql> show variables like 'log_bin' ;
+ ---------------+-------+
| Variable_name | Value | + ---------------+-------+
| log_bin | ON |
+ ---------------+-------+
1 row in set (0.00 sec)
mysql> show variables like 'binlog_format' ;
+ ---------------+-------+
| Variable_name | Value | + ---------------+-------+
| binlog_format | ROW | + ---------------+-------+
1 row in set (0.00 sec)
mysql> show variables like 'binlog_row_image' ;
+ ------------------+-------+
| Variable_name | Value | + ------------------+-------+
| binlog_row_image | FULL |
+ ------------------+-------+
1 row in set (0.00 sec)
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3. 闪回实战
* 创建数据库与测试表,并插入数据
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mysql> create table users(
-> id BIGINT NOT NULL AUTO_INCREMENT,
-> name VARCHAR (255) NOT NULL ,
-> sex ENUM( 'M' , 'F' ) NOT NULL DEFAULT 'M' ,
-> age INT UNSIGNED NOT NULL DEFAULT '0' ,
-> PRIMARY KEY (id)
-> )ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
Query OK, 0 rows affected (0.04 sec)
mysql> insert into users values ( null , 'tom' , 'M' , 25), ( null , 'jak' , 'F' , 32), ( null , 'ses' , 'M' , 45), ( null , 'lisea' , 'M' , 35);
Query OK, 4 rows affected (0.13 sec)
Records: 4 Duplicates: 0 Warnings: 0 mysql> select * from users;
+ ----+-------+-----+-----+
| id | name | sex | age |
+ ----+-------+-----+-----+
| 1 | tom | M | 25 | | 2 | jak | F | 32 | | 3 | ses | M | 45 | | 4 | lisea | M | 35 | + ----+-------+-----+-----+
4 rows in set (0.00 sec)
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* 下载闪回工具binlog2sql[ 由上海美团DBA团队出品 ]
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[[email protected] ~] # git clone https://github.com/danfengcao/binlog2sql.git
Initialized empty Git repository in /root/binlog2sql/ .git/
remote: Counting objects: 244, done .
remote: Total 244 (delta 0), reused 0 (delta 0), pack-reused 244 Receiving objects: 100% (244 /244 ), 121.72 KiB | 27 KiB /s , done .
Resolving deltas: 100% (124 /124 ), done .
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* 安装相关依赖
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[[email protected] ~] # yum install pip -y
[[email protected] ~] # pip install --upgrade pip
[[email protected] ~] # pip install -r binlog2sql/requirements.txt
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* 提前刷新binlog [ 测试中好区分文件 ]
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mysql> flush logs; Query OK, 0 rows affected (0.02 sec)
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* 查看当前binlog信息
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mysql> show master status; + ------------+----------+--------------+------------------+-------------------------------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set | + ------------+----------+--------------+------------------+-------------------------------------------+
| bin.000006 | 191 | | | c7f82640-6b2d-11e7-9316-000c29f0b169:1-22 | + ------------+----------+--------------+------------------+-------------------------------------------+
1 row in set (0.01 sec)
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* 误操作,delete没带where条件
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mysql> delete from users ;
Query OK, 4 rows affected (0.01 sec) |
* binlog2sql工具通过文件输出操作信息,定位SQL开始位置与结束位置
可通过--start-datetime与--stop-datetime定位时间
由此得到开始position为239,结束position为483
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[[email protected] ~]# python binlog2sql/binlog2sql/binlog2sql.py -hlocalhost -P3306 -uroot -p '123' -dmytest -tusers --start-file='bin.000006'
DELETE FROM `mytest`.`users` WHERE `age`=25 AND `sex`= 'M' AND `id`=1 AND ` name `= 'tom' LIMIT 1; #start 239 end 483 time 2017-07-19 01:02:49
DELETE FROM `mytest`.`users` WHERE `age`=32 AND `sex`= 'F' AND `id`=2 AND ` name `= 'jak' LIMIT 1; #start 239 end 483 time 2017-07-19 01:02:49
DELETE FROM `mytest`.`users` WHERE `age`=45 AND `sex`= 'M' AND `id`=3 AND ` name `= 'ses' LIMIT 1; #start 239 end 483 time 2017-07-19 01:02:49
DELETE FROM `mytest`.`users` WHERE `age`=35 AND `sex`= 'M' AND `id`=4 AND ` name `= 'lisea' LIMIT 1; #start 239 end 483 time 2017-07-19 01:02:49
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* binlog2sql通过flashback生成回滚SQL
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[[email protected] ~] # python binlog2sql/binlog2sql/binlog2sql.py -hlocalhost -P3306 -uroot -p'123' -dmytest -tusers --start-file='bin.000006' --start-position=239 --stop-position=483 -B > rollback.sql
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* 导入回滚SQL [ 导入前检查SQL语句是否正常 ]
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[[email protected] ~] # mysql -hlocalhost -uroot -p'123' < rollback.sql
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* 查看
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mysql> select * from mytest.users;
+ ----+-------+-----+-----+
| id | name | sex | age |
+ ----+-------+-----+-----+
| 1 | tom | M | 25 | | 2 | jak | F | 32 | | 3 | ses | M | 45 | | 4 | lisea | M | 35 | + ----+-------+-----+-----+
4 rows in set (0.00 sec)
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4. 总结
以需求驱动技术,技术本身没有优略之分,只有业务之分。
本文转自asd1123509133 51CTO博客,原文链接:http://blog.51cto.com/lisea/1949859,如需转载请自行联系原作者