Mysql实现增量恢复的方法详解

2020-01-18 21:11:01

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实验介绍

增量恢复一般适用的场景：

1、人为的sql语句破坏了数据库

2、在进行下一次完全备份之前发生系统故障导致数据库数据丢失

3、在主从架构中，主库数据发生了故障

丢失完全备份之后更改的数据的恢复步骤

1、首先做一个完全备份，确保生成完全备份的sql文件。

mysql> select * from yx;  #完全备份前数据库+----------+--------+| name   | score |+----------+--------+| zhangsan | 100.00 || lisi   | 90.00 || wangwu  | 80.00 || zhaoliu | 99.00 |+----------+--------+4 rows in set (0.00 sec)[root@promote data]# mysqldump -u root -p test > /opt/test.sql  #对数据库完全备份

2、使用flush-logs生成新的二进制日志文件，用以保存之后的数据库操作语句。

[root@promote data]# mysqladmin -u root -p flush-logs #生成二进制文件
Enter password:
[root@promote data]# ls
auto.cnf ibdata1 ib_logfile1 mysql mysql-bin.index sys
ib_buffer_pool ib_logfile0 ibtmp1 mysql-bin.000001 performance_schema test

3、在数据库中插入一条记录，再执行flush-logs操作，生成新的二进制增量备份文件。

mysql> insert into yx(name,score) values('tom',87);
Query OK, 1 row affected (0.00 sec)

mysql> select * from yx;
+----------+--------+
| name     | score |
+----------+--------+
| zhangsan | 100.00 |
| lisi     | 90.00 |
| wangwu   | 80.00 |
| zhaoliu | 99.00 |
| tom      | 87.00 |
+----------+--------+
5 rows in set (0.00 sec)
[root@promote data]# mysqladmin -u root -p flush-logs #生成二进制文件
Enter password:
[root@promote data]# ls
auto.cnf        ibdata1      ib_logfile1 mysql             mysql-bin.000002 performance_schema test
ib_buffer_pool ib_logfile0 ibtmp1       mysql-bin.000001 mysql-bin.index   sys

4、用delete删除刚才插入的数据。模拟完全备份后数据丢失。

mysql> delete from yx where name='tom';
Query OK, 1 row affected (0.00 sec)

mysql> select * from yx;
+----------+--------+
| name     | score |
+----------+--------+
| zhangsan | 100.00 |
| lisi     | 90.00 |
| wangwu   | 80.00 |
| zhaoliu | 99.00 |
+----------+--------+
4 rows in set (0.00 sec)

5、使用二进制文件进行恢复操作

[root@promote data]# mysqlbinlog --no-defaults mysql-bin.000001 | mysql -u root -p

6、查看数据库内容，删除的数据有了。说明数据恢复成功。

mysql> select * from yx;
+----------+--------+
| name     | score |
+----------+--------+
| zhangsan | 100.00 |
| lisi     | 90.00 |
| wangwu   | 80.00 |
| zhaoliu | 99.00 |
| tom      | 87.00 |
+----------+--------+
5 rows in set (0.00 sec）

完全备份之后丢失所有数据的恢复步骤

1、使用drop删除表yx，模拟数据完全丢失

mysql> drop table yx;
Query OK, 0 rows affected (0.01 sec)

mysql> show tables;
Empty set (0.00 sec)

2、先使用mysql命令进行完全备份恢复操作。

[root@promote data]# mysql -u root -p test < /opt/test.sql
mysql> use test;
Database changed
mysql> select * from yx;
+----------+--------+
| name     | score |
+----------+--------+
| zhangsan | 100.00 |
| lisi     | 90.00 |
| wangwu   | 80.00 |
| zhaoliu | 99.00 |
+----------+--------+
4 rows in set (0.00 sec)

3、使用二进制文件进行增量备份操作。

[root@promote data]# mysqlbinlog --no-defaults mysql-bin.000001 | mysql -u root -p
mysql> select * from yx;
+----------+--------+
| name     | score |
+----------+--------+
| zhangsan | 100.00 |
| lisi     | 90.00 |
| wangwu   | 80.00 |
| zhaoliu | 99.00 |
| tom      | 87.00 |
+----------+--------+
5 rows in set (0.00 sec)

基于时间点与位置的恢复

利用二进制日志实现局域时间点与位置的恢复，假如需要往数据库中插入两条数据，但是由于误操作，两条插入语句中间删除一条数据，而这条数据不应该删除，这时候，需要基于时间点与位置进行恢复。

start-datetime=datetime

从二进制日志中第1个日期时间等于或晚于datetime参量的事件开始读。

stop-datetime=datetime
从二进制日志中第1个日期时间等于或晚于datetime参量的事件起停止读。

start-position=N从二进制日志中第1个位置等于N参量时的事件开始读。

stop-position=N从二进制日志中第1个位置等于和大于N参量时的事件起停止读。

mysql> select * from yx;
+----------+--------+
| name     | score |
+----------+--------+
| zhangsan | 100.00 |
| lisi     | 90.00 |
| wangwu   | 80.00 |
| zhaoliu | 99.00 |
+----------+--------+
5 rows in set (0.00 sec)

mysql> insert into yx values('test01',87);
Query OK, 1 row affected (0.00 sec)

mysql> delete from yx where name='zhangsan';
Query OK, 1 row affected (0.00 sec)

mysql> insert into yx values('test02',99);
Query OK, 1 row affected (0.17 sec)

mysql> select * from yx;
+---------+-------+
| name | score |
+---------+-------+
| lisi | 90.00 |
| wangwu | 80.00 |
| zhaoliu | 99.00 |
| test01 | 87.00 |
| test02 | 99.00 |
+---------+-------+
6 rows in set (0.00 sec)

1、基于时间点的恢复。18-07-03 21:56:04是错误语句节点，18-07-03 21:56:11第二句正确语句节点

[root@promote data]# mysqlbinlog --no-defaults --base64-output=decode-rows mysql-bin.000003
# at 298
#180703 21:55:35 server id 1 end_log_pos 406 CRC32 0x257c67ab Query   thread_id=46    exec_time=0 error_code=0
use `test`/*!*/;
SET TIMESTAMP=1530626135/*!*/;
insert into yx values('test01',87)
/*!*/;
# at 406
#180703 21:55:35 server id 1 end_log_pos 437 CRC32 0xdd7913a3 Xid = 392
COMMIT/*!*/;
# at 437
#180703 21:56:04 server id 1 end_log_pos 502 CRC32 0x0d09bd0b Anonymous_GTID last_committed=1    sequence_number=2
SET @@SESSION.GTID_NEXT= 'ANONYMOUS'/*!*/;
# at 502
#180703 21:56:04 server id 1 end_log_pos 581 CRC32 0xe6040c79 Query   thread_id=46    exec_time=0 error_code=0
SET TIMESTAMP=1530626164/*!*/;
BEGIN
/*!*/;
# at 581
#180703 21:56:04 server id 1 end_log_pos 691 CRC32 0x2d99f699 Query   thread_id=46    exec_time=0 error_code=0
SET TIMESTAMP=1530626164/*!*/;
delete from yx where name='zhangsan'
/*!*/;
# at 691
#180703 21:56:04 server id 1 end_log_pos 722 CRC32 0x4a742173 Xid = 393
COMMIT/*!*/;
# at 722
#180703 21:56:11 server id 1 end_log_pos 787 CRC32 0x6d0b47d8 Anonymous_GTID last_committed=2    sequence_number=3
SET @@SESSION.GTID_NEXT= 'ANONYMOUS'/*!*/;
# at 787
#180703 21:56:11 server id 1 end_log_pos 866 CRC32 0x97e2deb7 Query   thread_id=46    exec_time=0 error_code=0
SET TIMESTAMP=1530626171/*!*/;
BEGIN
/*!*/;
# at 866
#180703 21:56:11 server id 1 end_log_pos 974 CRC32 0x9e24e8af Query   thread_id=46    exec_time=0 error_code=0
SET TIMESTAMP=1530626171/*!*/;
insert into yx values('test02',99)
[root@promote data]# mysql -u root -p test < /opt/test.sql   #先进行完全恢复
mysql> select * from yx;
+----------+--------+
| name     | score |
+----------+--------+
| zhangsan | 100.00 |
| lisi     | 90.00 |
| wangwu   | 80.00 |
| zhaoliu | 99.00 |
+----------+--------+
4 rows in set (0.00 sec)
[root@promote data]# mysqlbinlog --no-defaults --stop-datetime='18-07-03 21:56:04' mysql-bin.000003 | mysql -u root -p   #结束节点
Enter password:
[root@promote data]# mysqlbinlog --no-defaults --start-datetime='18-07-03 21:56:11' mysql-bin.000003 | mysql -u root -p   #重新开始节点
Enter password:
mysql> select * from yx;
+----------+--------+
| name     | score |
+----------+--------+
| zhangsan | 100.00 |
| lisi     | 90.00 |
| wangwu   | 80.00 |
| zhaoliu | 99.00 |
| test01   | 87.00 |
| test02   | 99.00 |
+----------+--------+
6 rows in set (0.00 sec)

2、基于位置恢复，其中581是错误语句的节点，866是第二句正确语句的节点

[root@promote data]# mysql -u root -p test < /opt/test.sql
mysql> select * from yx;
+----------+--------+
| name     | score |
+----------+--------+
| zhangsan | 100.00 |
| lisi     | 90.00 |
| wangwu   | 80.00 |
| zhaoliu | 99.00 |
+----------+--------+
4 rows in set (0.01 sec)
[root@promote data]# mysqlbinlog --no-defaults --stop-position='581' mysql-bin.000003 | mysql -u root -p
Enter password:
[root@promote data]# mysqlbinlog --no-defaults --start-position='866' mysql-bin.000003 | mysql -u root -p
Enter password:
mysql> select * from yx;
+----------+--------+
| name     | score |
+----------+--------+
| zhangsan | 100.00 |
| lisi     | 90.00 |
| wangwu   | 80.00 |
| zhaoliu | 99.00 |
| test01   | 87.00 |
| test02   | 99.00 |
+----------+--------+
6 rows in set (0.00 sec)