从完整备份恢复单个innodb表

Posted 2020-09-06 技术为王

从完整备份恢复单个innodb表

转载自：http://www.cnblogs.com/gomysql/p/6600616.html#top

大师兄的博客

现在大多数同学在线上采取的备份策略都是xtrabackup全备+binlog备份，那么当某天某张表意外的删除那么如何从xtrabackup全备中恢复呢？从mysql 5.6版本开始，支持可移动表空间（Transportable Tablespace）那么利用这个功能就可以实现单表的恢复，同样利用这个功能还可以把innodb表移动到另外一台服务器上。可以参考：https://yq.aliyun.com/articles/59271

下面进行从xtrabackup全备恢复单表的测试。

1. 开启了参数innodb_file_per_table

2. 安装工具：mysql-utilities，其中mysqlfrm可以读取表结构。

yum install mysql-utilities -y

查看原表中的数据：

mysql> select * from yayun.t1;
+------+------+
| id   | name |
+------+------+
|    1 | aa   |
|    2 | bb   |
|    3 | cc   |
|    4 | dd   |
+------+------+
4 rows in set (0.00 sec)

mysql> 

执行备份：

innobackupex --defaults-file=/data/mysql/3306/my.cnf --user=root --password=123 --sock=/data/mysql/3306/mysqltmp/mysql.sock /data/

apply-log

innobackupex --defaults-file=/data/mysql/3306/my.cnf --apply-log /data/2017-03-22_16-13-00/

删除t1表：

mysql> use yayun
Database changed
mysql> drop table t1;
Query OK, 0 rows affected (0.13 sec)

mysql> 

读取表结构

mysqlfrm --diagnostic /data/2017-03-22_16-13-00/yayun/t1.frm 

输出：

# Reading .frm file for /data/2017-03-22_16-13-00/yayun/t1.frm:
# The .frm file is a TABLE.
# CREATE TABLE Statement:

CREATE TABLE `yayun`.`t1` (
  `id` int(11) DEFAULT NULL, 
  `name` char(180) DEFAULT NULL 
) ENGINE=InnoDB;

#...done.

建表:

mysql> use yayun
Database changed
mysql> CREATE TABLE `yayun`.`t1` (
    ->   `id` int(11) DEFAULT NULL, 
    ->   `name` char(180) DEFAULT NULL 
    -> ) ENGINE=InnoDB;
Query OK, 0 rows affected (0.08 sec)

mysql> 

加一个写锁，确保安全

mysql> lock tables t1 write;       
Query OK, 0 rows affected (0.00 sec)

mysql> 

丢弃表空间：

mysql> alter table t1 discard tablespace;       
Query OK, 0 rows affected (0.07 sec)

mysql> 

从备份中拷贝ibd文件，并且修改权限

[root@db_server_yayun_01 ~]# cp /data/2017-03-22_16-13-00/yayun/t1.ibd /data/mysql/3306/data/yayun/
[root@db_server_yayun_01 ~]# chown -R mysql.mysql /data/mysql/3306/data/yayun/t1.ibd 

载入表空间：

mysql> alter table t1 import tablespace;       
Query OK, 0 rows affected, 1 warning (0.15 sec)

mysql> show warnings;
+---------+------+------------------------------------------------------------------------------------------------------------------------------------------+
| Level   | Code | Message                                                                                                                                  |
+---------+------+------------------------------------------------------------------------------------------------------------------------------------------+
| Warning | 1810 | InnoDB: IO Read error: (2, No such file or directory) Error opening \'./yayun/t1.cfg\', will attempt to import without schema verification |
+---------+------+------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

mysql> 

这里有警告，可以忽略。详情可以看：https://yq.aliyun.com/articles/59271
查询数据是否一致：

mysql> select * from t1;
+------+------+
| id   | name |
+------+------+
|    1 | aa   |
|    2 | bb   |
|    3 | cc   |
|    4 | dd   |
+------+------+
4 rows in set (0.00 sec)

mysql> 

最后解锁：

mysql> unlock tables;
Query OK, 0 rows affected (0.00 sec)

mysql> 

 

mysql-utilities是一个用python2.6写的一个工具集
root@VM_45_133_centos ~]# rpm -qa |grep mysql-utilities
mysql-utilities-1.3.6-1.el6.noarch
[root@VM_45_133_centos ~]# rpm -ql mysql-utilities
/usr/bin/mysqlauditadmin
/usr/bin/mysqlauditgrep
/usr/bin/mysqldbcompare
/usr/bin/mysqldbcopy
/usr/bin/mysqldbexport
/usr/bin/mysqldbimport
/usr/bin/mysqldiff
/usr/bin/mysqldiskusage
/usr/bin/mysqlfailover
/usr/bin/mysqlfrm
/usr/bin/mysqlindexcheck
/usr/bin/mysqlmetagrep
/usr/bin/mysqlprocgrep
/usr/bin/mysqlreplicate
/usr/bin/mysqlrpladmin
/usr/bin/mysqlrplcheck
/usr/bin/mysqlrplshow
/usr/bin/mysqlserverclone
/usr/bin/mysqlserverinfo
/usr/bin/mysqluc
/usr/bin/mysqluserclone

 

参考文章：

https://www.percona.com/blog/2017/03/15/restore-single-innodb-table-full-backup-accidentally-dropping/