数据库的备份与还原系列——单表备份和恢复详细完整实现

参考实现：

https://www.percona.com/doc/percona-xtrabackup/LATEST/innobackupex/innobackupex_script.html

Restoring Individual Tables#5.6之前是不支持的；In server versions prior to 5.6, it is not possible to copy tables between servers by copying the files, even with innodb_file_per_table.However, with the Percona XtraBackup, you can export individual tables from any InnoDB database, and import them into Percona Server with XtraDB or MySQL 5.6 (The source doesn't have to be XtraDB or or MySQL 5.6,but the destination does). This only works on individual .ibd files, and cannot export a table that is not contained in its own .ibd file.

数据备份：

[root@centos7x ~]$systemctl start mariadb[root@centos7x ~]$mysql < hellodb_InnoDB.sql 默认的每个表一个文件；[root@centos7x ~]$ll /var/lib/mysql/total 122936-rw-rw---- 1 mysql mysql    16384 Feb 25 16:11 aria_log.00000001-rw-rw---- 1 mysql mysql       52 Feb 25 16:11 aria_log_control-rw-rw---- 1 mysql mysql        5 Feb 25 16:18 centos7x.piddrwx------ 2 mysql mysql      272 Feb 25 16:18 hellodb-rw-rw---- 1 mysql mysql     2795 Feb 25 16:11 ib_buffer_pool-rw-rw---- 1 mysql mysql 12582912 Feb 25 16:18 ibdata1-rw-rw---- 1 mysql mysql 50331648 Feb 25 16:18 ib_logfile0-rw-rw---- 1 mysql mysql 50331648 Feb 25 16:11 ib_logfile1-rw-rw---- 1 mysql mysql 12582912 Feb 25 16:18 ibtmp1-rw-rw---- 1 mysql mysql        0 Feb 25 16:18 multi-master.infodrwx--x--x 2 mysql mysql     4096 Feb 25 16:11 mysqlsrwxrwxrwx 1 mysql mysql        0 Feb 25 16:18 mysql.sockdrwx------ 2 mysql mysql       20 Feb 25 16:11 performance_schema-rw-rw---- 1 mysql mysql    24576 Feb 25 16:18 tc.logdrwxr-xr-x 2 mysql mysql        6 Feb 25 16:11 test[root@centos7x ~]$ll /var/lib/mysql/hellodb/total 704-rw-rw---- 1 mysql mysql  1277 Feb 25 16:18 classes.frm-rw-rw---- 1 mysql mysql 98304 Feb 25 16:18 classes.ibd-rw-rw---- 1 mysql mysql   976 Feb 25 16:18 coc.frm-rw-rw---- 1 mysql mysql 98304 Feb 25 16:18 coc.ibd-rw-rw---- 1 mysql mysql  1251 Feb 25 16:18 courses.frm-rw-rw---- 1 mysql mysql 98304 Feb 25 16:18 courses.ibd-rw-rw---- 1 mysql mysql    61 Feb 25 16:18 db.opt-rw-rw---- 1 mysql mysql  1001 Feb 25 16:18 scores.frm-rw-rw---- 1 mysql mysql 98304 Feb 25 16:18 scores.ibd-rw-rw---- 1 mysql mysql  1208 Feb 25 16:18 students.frm-rw-rw---- 1 mysql mysql 98304 Feb 25 16:18 students.ibd-rw-rw---- 1 mysql mysql  1298 Feb 25 16:18 teachers.frm-rw-rw---- 1 mysql mysql 98304 Feb 25 16:18 teachers.ibd-rw-rw---- 1 mysql mysql   973 Feb 25 16:18 toc.frm-rw-rw---- 1 mysql mysql 98304 Feb 25 16:18 toc.ibd[root@centos7x ~]$mkdir -pv /backupsmkdir: created directory '/backups'[root@centos7x ~]$innobackupex --include='hellodb.students' /backups/这只是备份了数据了；[root@centos7x ~]$ll /backups/2018-02-25_16-23-08/hellodb/total 100-rw-r----- 1 root root  1208 Feb 25 16:23 students.frm-rw-r----- 1 root root 98304 Feb 25 16:23 students.ibd

备份表定义：

所以需要将表定义也导出来；否则将来的恢复过程是需要创建表定义的；[root@centos7x ~]$mysql -e 'show create table hellodb.students\G;'*************************** 1. row ***************************       Table: studentsCreate Table: CREATE TABLE `students` (  `StuID` int(10) unsigned NOT NULL AUTO_INCREMENT,  `Name` varchar(50) NOT NULL,  `Age` tinyint(3) unsigned NOT NULL,  `Gender` enum('F','M') NOT NULL,  `ClassID` tinyint(3) unsigned DEFAULT NULL,  `TeacherID` int(10) unsigned DEFAULT NULL,  PRIMARY KEY (`StuID`)) ENGINE=InnoDB AUTO_INCREMENT=26 DEFAULT CHARSET=utf8

表破坏操作：

进行表的破坏；[root@centos7x ~]$mysql -e 'drop table hellodb.students;'    MariaDB [hellodb]> show tables;    +-------------------+    | Tables_in_hellodb |    +-------------------+    | classes           |    | coc               |    | courses           |    | scores            |    | teachers          |    | toc               |    +-------------------+    6 rows in set (0.00 sec)

数据和表定义恢复操作：

恢复操作：先整理；[root@centos7x ~]$innobackupex --apply-log --export /backups/2018-02-25_16-23-08/整理、导出数据的前后变化；[root@centos7x ~]$ll /backups/2018-02-25_16-23-08/hellodb/-rw-r----- 1 root root  1208 Feb 25 16:23 students.frm-rw-r----- 1 root root 98304 Feb 25 16:23 students.ibd[root@centos7x ~]$ll /backups/2018-02-25_16-23-08/hellodb/total 120-rw-r--r-- 1 root root   640 Feb 25 16:49 students.cfg-rw-r----- 1 root root 16384 Feb 25 16:49 students.exp-rw-r----- 1 root root  1208 Feb 25 16:23 students.frm-rw-r----- 1 root root 98304 Feb 25 16:23 students.ibd恢复表之前，先创建表结构；MariaDB [(none)]> use hellodb;Reading table information for completion of table and column namesYou can turn off this feature to get a quicker startup with -ADatabase changedMariaDB [hellodb]> CREATE TABLE `students` (    ->   `StuID` int(10) unsigned NOT NULL AUTO_INCREMENT,    ->   `Name` varchar(50) NOT NULL,    ->   `Age` tinyint(3) unsigned NOT NULL,    ->   `Gender` enum('F','M') NOT NULL,    ->   `ClassID` tinyint(3) unsigned DEFAULT NULL,    ->   `TeacherID` int(10) unsigned DEFAULT NULL,    ->   PRIMARY KEY (`StuID`)    -> ) ENGINE=InnoDB AUTO_INCREMENT=26 DEFAULT CHARSET=utf8;Query OK, 0 rows affected (0.01 sec)MariaDB [hellodb]> select * from students;Empty set (0.00 sec)MariaDB [hellodb]> desc students;+-----------+---------------------+------+-----+---------+----------------+| Field     | Type                | Null | Key | Default | Extra          |+-----------+---------------------+------+-----+---------+----------------+| StuID     | int(10) unsigned    | NO   | PRI | NULL    | auto_increment || Name      | varchar(50)         | NO   |     | NULL    |                || Age       | tinyint(3) unsigned | NO   |     | NULL    |                || Gender    | enum('F','M')       | NO   |     | NULL    |                || ClassID   | tinyint(3) unsigned | YES  |     | NULL    |                || TeacherID | int(10) unsigned    | YES  |     | NULL    |                |+-----------+---------------------+------+-----+---------+----------------+6 rows in set (0.00 sec)此时虽然有表结构和数据文件，但是没有数据；[root@centos7x ~]$ll /var/lib/mysql/hellodb/ -htotal 704K-rw-rw---- 1 mysql mysql 1.3K Feb 25 16:18 classes.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 classes.ibd-rw-rw---- 1 mysql mysql  976 Feb 25 16:18 coc.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 coc.ibd-rw-rw---- 1 mysql mysql 1.3K Feb 25 16:18 courses.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 courses.ibd-rw-rw---- 1 mysql mysql   61 Feb 25 16:18 db.opt-rw-rw---- 1 mysql mysql 1001 Feb 25 16:18 scores.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 scores.ibd-rw-rw---- 1 mysql mysql 1.2K Feb 25 16:53 students.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:53 students.ibd-rw-rw---- 1 mysql mysql 1.3K Feb 25 16:18 teachers.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 teachers.ibd-rw-rw---- 1 mysql mysql  973 Feb 25 16:18 toc.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 toc.ibd于是要删除这个表空间文件，即数据文件；但是不要使用rm删除，而是使用命令删除；MariaDB [hellodb]> alter table students discard tablespace;Query OK, 0 rows affected (0.00 sec)[root@centos7x ~]$ll /var/lib/mysql/hellodb/ -htotal 608K-rw-rw---- 1 mysql mysql 1.3K Feb 25 16:18 classes.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 classes.ibd-rw-rw---- 1 mysql mysql  976 Feb 25 16:18 coc.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 coc.ibd-rw-rw---- 1 mysql mysql 1.3K Feb 25 16:18 courses.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 courses.ibd-rw-rw---- 1 mysql mysql   61 Feb 25 16:18 db.opt-rw-rw---- 1 mysql mysql 1001 Feb 25 16:18 scores.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 scores.ibd-rw-rw---- 1 mysql mysql 1.2K Feb 25 16:53 students.frm-rw-rw---- 1 mysql mysql 1.3K Feb 25 16:18 teachers.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 teachers.ibd-rw-rw---- 1 mysql mysql  973 Feb 25 16:18 toc.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 toc.ibd[root@centos7x ~]$cp /backups/2018-02-25_16-23-08/hellodb/students.{cfg,ibd,exp} /var/lib/mysql/hellodb/[root@centos7x ~]$ll /var/lib/mysql/hellodb/ -htotal 724K-rw-rw---- 1 mysql mysql 1.3K Feb 25 16:18 classes.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 classes.ibd-rw-rw---- 1 mysql mysql  976 Feb 25 16:18 coc.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 coc.ibd-rw-rw---- 1 mysql mysql 1.3K Feb 25 16:18 courses.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 courses.ibd-rw-rw---- 1 mysql mysql   61 Feb 25 16:18 db.opt-rw-rw---- 1 mysql mysql 1001 Feb 25 16:18 scores.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 scores.ibd-rw-r--r-- 1 root  root   640 Feb 25 16:59 students.cfg-rw-r----- 1 root  root   16K Feb 25 16:59 students.exp-rw-rw---- 1 mysql mysql 1.2K Feb 25 16:53 students.frm-rw-r----- 1 root  root   96K Feb 25 16:59 students.ibd-rw-rw---- 1 mysql mysql 1.3K Feb 25 16:18 teachers.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 teachers.ibd-rw-rw---- 1 mysql mysql  973 Feb 25 16:18 toc.frm-rw-rw---- 1 mysql mysql  96K Feb 25 16:18 toc.ibd[root@centos7x ~]$chown -R mysql.mysql /var/lib/mysql/hellodb/接着是导入表空间，尽管文件放在数据目录下了，但是表空间还没有关联；MariaDB [hellodb]> alter table students import tablespace;Query OK, 0 rows affected (0.02 sec)

数据和表结构验证操作：

验证；MariaDB [hellodb]> select * from students;+-------+---------------+-----+--------+---------+-----------+| StuID | Name          | Age | Gender | ClassID | TeacherID |+-------+---------------+-----+--------+---------+-----------+|     1 | Shi Zhongyu   |  22 | M      |       2 |         3 ||     2 | Shi Potian    |  22 | M      |       1 |         7 ||     3 | Xie Yanke     |  53 | M      |       2 |        16 ||     4 | Ding Dian     |  32 | M      |       4 |         4 |