MySQL单表ibd文件恢复方法详解

时间:2021-07-27 07:36:51

前言: 
随着innodb的普及,innobackup也成为了主流备份方式。物理备份对于新建slave,全库恢复的需求都能从容应对。 
但当面临单表数据误删,或者单表误drop的情况,如果使用物理全备进行恢复呢? 
下文将进行详细分析。 
恢复过程中需要用到的工具,percona data recover tool : https://launchpad.net/percona-innodb-recovery-tool 

情况一:误删部分数据,需要用最近一次备份覆盖 
来自同一台机器的ibd恢复覆盖,且备份后table没有被recreate过。 
这种情况是最简单的,备份时的ibd文件(后称老ibd)中的space id和index id 与 新ibd的space id 和index id一致。 
且和ibdata文件中的space id和index id一致。因此,物理文件可以直接覆盖做恢复。 
以下是详细步骤 

Step -1 : 物理备份 
innobackupex --defaults-file=/usr/local/mysql3321/my.cnf --socket=/xfs/mysql3321/mysql.sock --user=root --password=password /xfs/backup/ 
Step 0 : apply log 
innobackupex --apply-log --defaults-file=/usr/local/mysql3321/my.cnf /xfs/backup/2012-10-17_11-29-20/ 
Step 1 : 备份现在的ibd文件(可选) 
cp -a testibd.ibd testibd.bak 
Step 2 : 舍弃现在ibd文件 
mysql> alter table testibd discard tablespace 
Step 3 : 复制备份ibd文件 
shell> cp /xfs/backup/2012-10-17_11-29-20/test/testibd.ibd /xfs/mysql3321/test/ 
shell> chown mysql:mysql /xfs/mysql3321/test/testibd.ibd 
Step 4 : 导入ibd文件 
mysql> alter table testibd import tablespace 

情况二:误删 table,表结构已经被drop了 
这种情况稍复杂,不过恢复过程还是比较容易操作的。由于table被drop后的space id会留空因此备份文件的space id不会被占用。 
我们只需要重建表结构,然后把ibdata中该表的space id还原,物理文件可以直接覆盖做恢复了。 

Step 1 : 重建表 
mysql> create table testibd (UserID int); 
Step 2 : 关闭mysql服务(必须) 
shell> service mysqld3321 stop 
Step 3: 准备ibd文件 apply log 
shell> innobackupex --apply-log --defaults-file=/usr/local/mysql3321/my.cnf /xfs/backup/2012-10-17_11-29-20/ 
Step 4 : 备份现在的ibd文件(可选) 
cp -a testibd.ibd testibd.bak 
Step 5 : 复制备份ibd文件 
shell> cp -a /xfs/backup/2012-10-17_11-29-20/test/testibd.ibd /xfs/mysql3321/test/ 
shell> chown mysql:mysql /xfs/mysql3321/test/testibd.ibd 
Step 6 : 使用percona recovery tool 修改ibdata 
shell> /root/install/percona-data-recovery-tool-for-innodb-0.5/ibdconnect -o /xfs/mysql3321/ibdata1 -f /xfs/mysql3321/test/testibd.ibd -d test -t testibd 

复制代码代码如下:


Initializing table definitions... 
Processing table: SYS_TABLES 
- total fields: 10 
- nullable fields: 6 
- minimum header size: 5 
- minimum rec size: 21 
- maximum rec size: 555 
Processing table: SYS_INDEXES 
- total fields: 9 
- nullable fields: 5 
- minimum header size: 5 
- minimum rec size: 29 
- maximum rec size: 165 
Setting SPACE=1 in SYS_TABLE for `test`.`testibd` 
Check if space id 1 is already used 
Page_id: 8, next page_id: 4294967295 
Record position: 65 
Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 8 50 3 2 0 0 0 0 0 
Db/table: infimum 
Space id: 1768842857 (0x696E6669) 
Next record at offset: 8D 
Record position: 8D 
Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 11 17 24 32 36 40 48 52 52 
Db/table: SYS_FOREIGN 
Space id: 0 (0x0) 
Next record at offset: D5 
Record position: D5 
Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 16 22 29 37 41 45 53 57 57 
Db/table: SYS_FOREIGN_COLS 
Space id: 0 (0x0) 
Next record at offset: 122 
Record position: 122 
Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 12 18 25 33 37 41 49 53 53 
Db/table: test/testibd 
Space id: 2 (0x2) 
Next record at offset: 74 
Space id 1 is not used in any of the records in SYS_TABLES 
Page_id: 8, next page_id: 4294967295 
Record position: 65 
Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 8 50 3 2 0 0 0 0 0 
Db/table: infimum 
Space id: 1768842857 (0x696E6669) 
Next record at offset: 8D 
Record position: 8D 
Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 11 17 24 32 36 40 48 52 52 
Db/table: SYS_FOREIGN 
Space id: 0 (0x0) 
Next record at offset: D5 
Record position: D5 
Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 16 22 29 37 41 45 53 57 57 
Db/table: SYS_FOREIGN_COLS 
Space id: 0 (0x0) 
Next record at offset: 122 
Record position: 122 
Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 12 18 25 33 37 41 49 53 53 
Db/table: test/testibd 
Space id: 2 (0x2) 
Updating test/testibd (table_id 17) with id 0x01000000 
SYS_TABLES is updated successfully 
Initializing table definitions... 
Processing table: SYS_TABLES 
- total fields: 10 
- nullable fields: 6 
- minimum header size: 5 
- minimum rec size: 21 
- maximum rec size: 555 
Processing table: SYS_INDEXES 
- total fields: 9 
- nullable fields: 5 
- minimum header size: 5 
- minimum rec size: 29 
- maximum rec size: 165 
Setting SPACE=1 in SYS_INDEXES for TABLE_ID = 17 
Page_id: 11, next page_id: 4294967295 
Record position: 65 
Checking field lengths for a row (SYS_INDEXES): OFFSETS: 15 8 50 7 2 0 0 0 0 
TABLE_ID: 3798561113125514496 
SPACE: 1768842857 
Next record at offset: 8C 
Record position: 8C 
Checking field lengths for a row (SYS_INDEXES): OFFSETS: 15 8 16 22 29 35 39 43 47 
TABLE_ID: 11 
SPACE: 0 
Next record at offset: CE 
Record position: CE 
Checking field lengths for a row (SYS_INDEXES): OFFSETS: 15 8 16 22 29 36 40 44 48 
TABLE_ID: 11 
SPACE: 0 
Next record at offset: 111 
Record position: 111 
Checking field lengths for a row (SYS_INDEXES): OFFSETS: 15 8 16 22 29 36 40 44 48 
TABLE_ID: 11 
SPACE: 0 
Next record at offset: 154 
Record position: 154 
Checking field lengths for a row (SYS_INDEXES): OFFSETS: 15 8 16 22 29 35 39 43 47 
TABLE_ID: 12 
SPACE: 0 
Next record at offset: 22C 
Record position: 22C 
Checking field lengths for a row (SYS_INDEXES): OFFSETS: 15 8 16 22 29 44 48 52 56 
TABLE_ID: 17 
SPACE: 2 
Updating SPACE(0x00000001 , 0x01000000) for TABLE_ID: 17 
sizeof(s)=4 
Next record at offset: 74 
SYS_INDEXES is updated successfully 


Step 7 : 使用percona recovery tool 重新checksum ibdata 
重复执行以下命令,直到程序没有输出为止。 
shell> /root/install/percona-data-recovery-tool-for-innodb-0.5/innochecksum -f /xfs/mysql3321/ibdata1 

复制代码代码如下:


page 8 invalid (fails old style checksum) 
page 8: old style: calculated = 0xF4AD74CB; recorded = 0xEECB309D 
fixing old checksum of page 8 
page 8 invalid (fails new style checksum) 
page 8: new style: calculated = 0x6F0C29B4; recorded = 0x3D02308C 
fixing new checksum of page 8 
page 11 invalid (fails old style checksum) 
page 11: old style: calculated = 0x3908087C; recorded = 0xF9E8D30C 
fixing old checksum of page 11 
page 11 invalid (fails new style checksum) 
page 11: new style: calculated = 0xB26CFD77; recorded = 0xDB25D39D 
fixing new checksum of page 11 


Step 8 : 启动mysql服务 
shell> service mysqld3321 start