如何利用MySQL的binlog恢复误删数据库详解

Shun

MySQL一旦误删数据库之后恢复数据很麻烦,这里记录一下艰辛的恢复过程,这篇文章主要给大家介绍了关于如何利用MySQL的binlog恢复误删数据库的相关资料,需要的朋友可以参考下
1 查看当前数据库内容并备份数据库
查看数据库信息：

备份数据库：

[root@localhost ~]# mysqldump -u root -p t > /mnt/t.sql
enter password: 
[root@localhost ~]# ll /mnt/t.sql 
-rw-r--r-- 1 root root 1771 aug 25 11:56 /mnt/t.sql

2 开启bin_log功能
首先查看数据库是否开启bin_log功能

mysql> show variables like "%log_bin%";

需要修改mysql的配置文件，/etc/的my.cnf，添加一句log_bin = mysql_bin即可

3 模拟误操作（插入3条数据，删除数据库）

mysql> insert into t1 values (3);
query ok, 1 row affected (0.00 sec)
 
mysql> insert into t1 values (4);
query ok, 1 row affected (0.00 sec)
 
mysql> insert into t1 values (5);
query ok, 1 row affected (0.00 sec)
 
mysql> select * from t1;
+------+
| id   |
+------+
|  1 |
|  2 |
|  5 |
|  4 |
|  3 |
+------+
5 rows in set (0.00 sec)
 
mysql> flush logs;
query ok, 0 rows affected (0.00 sec)
 
mysql> show master status;
+------------------+----------+--------------+------------------+
| file       | position | binlog_do_db | binlog_ignore_db |
+------------------+----------+--------------+------------------+
| mysql_bin.000003 |    106 |        |          |
+------------------+----------+--------------+------------------+
1 row in set (0.00 sec)

删除数据：

mysql> truncate t1;
query ok, 0 rows affected (0.00 sec)
 
mysql> select * from t1;
empty set (0.00 sec)

此时突然数据库损坏或者人为删除

mysql> drop table t1;
query ok, 0 rows affected (0.00 sec)
 
mysql> show tables;
empty set (0.00 sec)

4 数据恢复
1 用已经备份的/mnt/t.sql来恢复数据

mysql> source /mnt/t.sql;
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.01 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 2 rows affected (0.00 sec)
records: 2  duplicates: 0  warnings: 0
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
 
query ok, 0 rows affected (0.00 sec)
mysql> show tables;
+-------------+
| tables_in_t |
+-------------+
| t1      |
+-------------+
1 row in set (0.00 sec)
 
mysql> select * from t1;
+------+
| id   |
+------+
|  1 |
|  2 |
+------+
2 rows in set (0.00 sec)

2 还有三条数据没有恢复，怎么办。只能用bin-log来恢复

[root@localhost ~]# mysqlbinlog --no-defaults /var/lib/mysql/mysql_bin.000002 | mysql -u root -p123.com t

mysql> use t;
reading table information for completion of table and column names
you can turn off this feature to get a quicker startup with -a
 
database changed
mysql> select * from t1;
+------+
| id   |
+------+
|  1 |
|  2 |
|  3 |
|  4 |
|  5 |
+------+
5 rows in set (0.00 sec)
 
mysql>

5 总结
备份数据

mysqldump -uroot -p123456 test -l -f '/tmp/test.sql'
-l:读锁（只能读取，不能更新）
-f:即flush logs，可以重新生成新的日志文件，当然包括log-bin日志

查看binlog日志

mysql>show master status;

导入之前备份数据

mysql -uroot -p t -v -f </mnt/t.sql
-v查看导入的详细信息
-f是当中间遇到错误时，可以skip过去，继续执行下面的语句

恢复binlog-file二进制日志文件

mysqlbinlog --no-defaults binlog-file | mysql -uroot -p t

从某一(367)点开始恢复

mysqlbinlog --no-defaults --stop-position="367" mysql-bin.000001| mysql -uroot -p t

先查好那一点，用more来查看

[root@localhost mysql]# /usr/bin/mysqlbinlog --no-defaults mysql-bin.000002 --start-position="794" --stop-position="1055" | more

然后恢复

[root@localhost mysql]# /usr/bin/mysqlbinlog --no-defaults mysql-bin.000002 --start-position="794" --stop-position="1055" | /usr/bin/mysql -uroot -p t

重置binlog日志

mysql> reset master;
query ok, 0 rows affected (0.01 sec)
 
mysql> show master status;
+------------------+----------+--------------+------------------+
| file       | position | binlog_do_db | binlog_ignore_db |
+------------------+----------+--------------+------------------+
| mysql-bin.000001 |    106 |        |          |
+------------------+----------+--------------+------------------+

mysql> flush logs;#关闭当前的二进制日志文件并创建一个新文件，新的二进制日志文件的名字在当前的二进制文件的编号上加1。

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原文链接：https://juejin.cn/post/7012122461110009863