Centos7实现MySQL基于日志还原数据的示例代码

简介

Binlog日志，即二进制日志文件，用于记录用户对数据库操作的SQL语句信息，当发生数据误删除的时候我们可以通过binlog日志来还原已经删除的数据，还原数据的方法分为传统二进制文件还原数据和基于GTID的二进制文件还原数据

前期准备

准备一台Centos7虚拟机，关闭防火墙和selinux，配置IP地址,同步系统时间,安装MySQL数据库

传统二进制日志还原数据

修改配置文件

[root@localhost ~]# vi /etc/my.cnf
server-id=1
log-bin=binlog

#重启数据库服务
[root@localhost ~]# systemctl restart mysqld

操作数据库

mysql> create database mydb charset utf8mb4;
mysql> use mydb;
mysql> create table test(id int)engine=innodb charset=utf8mb4;
mysql> insert into test values(1);
mysql> insert into test values(2);
mysql> insert into test values(3);
mysql> insert into test values(4);
mysql> commit;
mysql> update test set id=10 where id=4;
mysql> commit;
mysql> select * from test;
+------+
| id  |
+------+
|  1 |
|  2 |
|  3 |
|  10 |
+------+
4 rows in set (0.00 sec)
mysql> drop database mydb;

查看二进制日志信息

mysql> show master statusG;
*************************** 1. row ***************************
File: binlog.000001
     Position: 1960
   Binlog_Do_DB: 
 Binlog_Ignore_DB: 
Executed_Gtid_Set: 
1 row in set (0.00 sec)

 
#查找创库和删库的点,为219和1868
mysql> show binlog events in 'binlog.000001';
+---------------+------+----------------+-----------+-------------+--------------------------------------------------------------------+
| Log_name   | Pos | Event_type   | Server_id | End_log_pos | Info    |
+---------------+------+----------------+-----------+-------------+--------------------------------------------------------------------+
| binlog.000001 | 219 | Query     |     1 |     329 | create database mydb charset utf8mb4  |
| binlog.000001 | 1868 | Query     |     1 |    1960 | drop database mydb    |
+---------------+------+----------------+-----------+-------------+--------------------------------------------------------------------+

另存为二进制日志信息

[root@localhost ~]# mysqlbinlog --start-position=219 --stop-position=1868 /var/lib/mysql/binlog.000001 > /tmp/binlog.sql

恢复数据

#临时关闭二进制日志记录以免重复记录
mysql> set sql_log_bin=0;
#恢复数据
mysql> source /tmp/binlog.sql
#重启二进制日志记录
mysql> set sql_log_bin=1;

查看数据恢复情况

mysql> show databases;
+--------------------+
| Database      |
+--------------------+
| information_schema |
| mydb |
| mysql|
| performance_schema |
| sys |
+--------------------+
5 rows in set (0.00 sec)

mysql> use mydb;
Database changed
mysql> select * from test;
+------+
| id  |
+------+
|  1 |
|  2 |
|  3 |
|  10 |
+------+
4 rows in set (0.00 sec)、

基于GTID二进制日志还原数据