Centos7实现MySQL基于日志还原数据的示例代码

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 *** 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

*** 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 status\G;
*************************** 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

修改配置文件

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

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

*** 作数据库

mysql> create database mydb1;
mysql> use mydb1;
Database changed
mysql> create table t1(id int)engine=innodb charset=utf8mb4;
mysql> insert into t1 values(1);
mysql> insert into t1 values(2);
mysql> insert into t1 values(3);
mysql> insert into t1 values(11);
mysql> insert into t1 values(12);
mysql> commit;
mysql> select * from t1;
+------+
| id  |
+------+
|  1 |
|  2 |
|  3 |
|  11 |
|  12 |
+------+
5 rows in set (0.00 sec)
mysql> drop database mydb1;

查看二进制日志信息

mysql> show master status\G;
*************************** 1. row ***************************
       File: binlog.000003
     Position: 1944
   Binlog_Do_DB: 
 Binlog_Ignore_DB: 
Executed_Gtid_Set: 51d3db57-bf69-11ea-976c-000c2911a022:1-8
1 row in set (0.00 sec)

mysql> show binlog events in 'binlog.000003';
+---------------+------+----------------+-----------+-------------+-------------------------------------------------------------------+
| Log_name   | Pos | Event_type   | Server_id | End_log_pos | Info                               |
+---------------+------+----------------+-----------+-------------+-------------------------------------------------------------------+
| binlog.000003 | 154 | Gtid      |     1 |     219 | SET @@SESSION.GTID_NEXT= '51d3db57-bf69-11ea-976c-000c2911a022:1' |
| binlog.000003 | 219 | Query     |     1 |     316 | create database mydb1                       |
| binlog.000003 | 1784 | Gtid      |     1 |    1849 | SET @@SESSION.GTID_NEXT= '51d3db57-bf69-11ea-976c-000c2911a022:8' |
| binlog.000003 | 1849 | Query     |     1 |    1944 | drop database mydb1                        |
+---------------+------+----------------+-----------+-------------+-------------------------------------------------------------------+

另存为二进制日志信息

#8号事务记录为删除数据库，因此只需恢复1-7号事务记录即可
[root@localhost ~]# mysqlbinlog --skip-gtids --include-gtids='51d3db57-bf69-11ea-976c-000c2911a022:1-7' /var/lib/mysql/binlog.000003 > /tmp/gtid.sql

参数说明:
--include-gtids:包含事务
--exclude-gtids:排除事务
--skip-gtids:跳过事务

恢复数据

mysql> set sql_log_bin=0;
mysql> source /tmp/gtid.sql
mysql> set sql_log_bin=1;

查看数据恢复情况

mysql> show databases;
+--------------------+
| Database      |
+--------------------+
| information_schema |
| mydb        |
| mydb1       |
| mysql       |
| performance_schema |
| sys        |
+--------------------+
6 rows in set (0.00 sec)

mysql> use mydb1;
Database changed
mysql> select * from t1;
+------+
| id  |
+------+
|  1 |
|  2 |
|  3 |
|  11 |
|  12 |
+------+
5 rows in set (0.00 sec)

 到此这篇关于Centos7实现MySQL基于日志还原数据的示例代码的文章就介绍到这了,更多相关Centos7 MySQL日志还原数据内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家！