修改MySQL的ib_logfile大小和组数

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标题:修改MySQL的ib_logfile大小和组数

作者:惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]

在某些情况下,需要修改MySQL的ib_logfile大小和组数(类似oracle redo),以下演示在MySQL 8.0修改ib_logfile大小和组数操作
查看当前ib_logfile情况

mysql> select version();
+-----------+
| version() |
+-----------+
| 8.0.21    |
+-----------+
1 row in set (0.00 sec)

mysql> show variables like '%innodb_log_file%';
+---------------------------+-----------+
| Variable_name             | Value     |
+---------------------------+-----------+
| innodb_log_file_size      | 134217728 |
| innodb_log_files_in_group | 2         |
+---------------------------+-----------+
2 rows in set, 1 warning (0.00 sec)

mysql> show variables like '%innodb_log_group_home_dir%';
+---------------------------+-------+
| Variable_name             | Value |
+---------------------------+-------+
| innodb_log_group_home_dir | .\    |
+---------------------------+-------+
1 row in set, 1 warning (0.00 sec)

mysql> show variables like '%datadir%';
+---------------+---------------+
| Variable_name | Value         |
+---------------+---------------+
| datadir       | E:\MySQL\8.0\ |
+---------------+---------------+
1 row in set, 1 warning (0.00 sec)

C:\Users\XFF>dir E:\MySQL\8.0\ib_log*
 驱动器 E 中的卷是 SSD
 卷的序列号是 98A5-7F8E

 E:\MySQL\8.0 的目录

2022-07-16  14:14       134,217,728 ib_logfile0
2022-07-03  17:30       134,217,728 ib_logfile1
               2 个文件    268,435,456 字节
               0 个目录 807,501,471,744 可用字节

当前ib_logfile成员为2个,每个128M,后续计划修改为成为3个,每个256M

修改my.ini参数

innodb_log_files_in_group=3
innodb_log_file_size=256M

重启mysql服务

C:\Users\XFF>dir E:\MySQL\8.0\ib_log*
 驱动器 E 中的卷是 SSD
 卷的序列号是 98A5-7F8E

 E:\MySQL\8.0 的目录

2022-07-16  14:19       268,435,456 ib_logfile0
2022-07-16  14:19       268,435,456 ib_logfile1
2022-07-16  14:19       268,435,456 ib_logfile2
               3 个文件    805,306,368 字节
               0 个目录 806,964,072,448 可用字节


mysql> show variables like '%innodb_log_file%';
+---------------------------+-----------+
| Variable_name             | Value     |
+---------------------------+-----------+
| innodb_log_file_size      | 268435456 |
| innodb_log_files_in_group | 3         |
+---------------------------+-----------+
2 rows in set, 1 warning (0.00 sec)

在8.0版本中直接修改成功,如果是以前MySQL版本,修改过程可能遭遇InnoDB: Error: log file ./ib_logfile0 is of different size 0 268435456 bytes错误,类似这样的需要删除ib_logfile文件,启动MySQL服务重新生成ib_logfile文件(在8.0版本中直接自动删除并重建)

mysql drop table 恢复

对于MySQL数据库的innodb引擎的数据库中,由于误操作删除表,或者由于sqldump自动生成语句含drop table create table语句导致数据丢失,在没有覆盖的情况下,可以实现完美恢复
创建测试表

mysql> CREATE TABLE recover.`t_drop` (
    ->   `messageId` varchar(30) NOT NULL,
    ->   `msgContent` varchar(1000) default NULL,
    ->   `scheduleDate` timestamp NOT NULL default CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
    ->   `deliverState` int(1) default NULL,
    ->   PRIMARY KEY  (`messageId`)
    -> ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
Query OK, 0 rows affected (0.00 sec)

mysql> insert into recover.t_drop select messageId,msgContent,scheduleDate,deliverState from sms_send_record;
Query OK, 11 rows affected (0.00 sec)
Records: 11  Duplicates: 0  Warnings: 0

mysql> select * from recover.`t_drop`;
+--------------------+----------------------------------------------------------------------------------+---------------------+--------------+
| messageId          | msgContent                                                                       | scheduleDate        | deliverState |
+--------------------+----------------------------------------------------------------------------------+---------------------+--------------+
| 10235259536125650  | 尊敬的用户您好:您的手机验证码为474851如非本人操作,请拨打奥斯卡客服:400-620-757    | 2010-01-01 00:00:00 |            0 | 
| 10235353811295807  | 尊敬的用户您好:您的手机验证码为444632如非本人操作,请拨打奥斯卡客服:400-620-757    | 2010-01-01 00:00:00 |            0 | 
| 102354211240398235 | 尊敬的用户您好:您的手机验证码为478503如非本人操作,请拨打奥斯卡客服:400-620-757    | 2010-01-01 00:00:00 |            0 | 
| 102354554052884567 | 尊敬的用户您好:您的手机验证码为216825如非本人操作,请拨打奥斯卡客服:400-620-757    | 2010-01-01 00:00:00 |            0 | 
| 132213454294519126 | 尊敬的用户您好:您的手机验证码为854812如非本人操作,请拨打奥斯卡客服:400-620-757    | 2010-01-01 00:00:00 |            0 | 
| 82329022242584577  | 尊敬的用户您好:您的手机验证码为253127如非本人操作,请拨打奥斯卡客服:400-620-757    | 2010-01-01 00:00:00 |            0 | 
| 82329022242584581  | 尊敬的用户您好:您的手机验证码为253127如非本人操作,请拨打奥斯卡客服:400-620-757    | 2010-01-01 00:00:00 |            0 | 
| 8233400415607376   | 尊敬的用户您好:您的手机验证码为338470如非本人操作,请拨打奥斯卡客服:400-620-757    | 2010-01-01 00:00:00 |            0 | 
| 82334502212106951  | 尊敬的用户您好:您的手机验证码为916515如非本人操作,请拨打奥斯卡客服:400-620-757    | 2010-01-01 00:00:00 |            0 | 
| 82339012756833423  | 尊敬的用户您好:您的手机验证码为396108如非本人操作,请拨打奥斯卡客服:400-620-757    | 2010-01-01 00:00:00 |            0 | 
| 8234322198577796   | 尊敬的用户您好:您的手机验证码为935297如非本人操作,请拨打奥斯卡客服:400-620-757    | 2010-01-01 00:00:00 |            0 | 
+--------------------+----------------------------------------------------------------------------------+---------------------+--------------+
11 rows in set (0.00 sec)

mysql> checksum table t_drop;
+-----------------+-----------+
| Table           | Checksum  |
+-----------------+-----------+
| recover.t_drop  | 920719058 | 
+-----------------+-----------+
1 row in set (0.00 sec)

删除测试表,后续用来恢复

mysql> drop table recover.t_drop;
Query OK, 0 rows affected (0.00 sec)

解析ibdata文件

[root@web103 mysql_recovery]# ./stream_parser -f /var/lib/mysql/ibdata1 
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         463312
time of last access:            1440825416 Sat Aug 29 13:16:56 2015
time of last modification:      1440855835 Sat Aug 29 21:43:55 2015
time of last status change:     1440855835 Sat Aug 29 21:43:55 2015
total size, in bytes:            236978176 (226.000 MiB)

Size to process:                 236978176 (226.000 MiB)
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         463312
time of last access:            1440825416 Sat Aug 29 13:16:56 2015
time of last modification:      1440855835 Sat Aug 29 21:43:55 2015
time of last status change:     1440855835 Sat Aug 29 21:43:55 2015
total size, in bytes:            236978176 (226.000 MiB)

Size to process:                 236978176 (226.000 MiB)
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         463312
time of last access:            1440825416 Sat Aug 29 13:16:56 2015
time of last modification:      1440855835 Sat Aug 29 21:43:55 2015
time of last status change:     1440855835 Sat Aug 29 21:43:55 2015
total size, in bytes:            236978176 (226.000 MiB)

Size to process:                 236978176 (226.000 MiB)
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         463312
time of last access:            1440825416 Sat Aug 29 13:16:56 2015
time of last modification:      1440855835 Sat Aug 29 21:43:55 2015
time of last status change:     1440855835 Sat Aug 29 21:43:55 2015
total size, in bytes:            236978176 (226.000 MiB)

Size to process:                 236978176 (226.000 MiB)
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         463312
time of last access:            1440825416 Sat Aug 29 13:16:56 2015
time of last modification:      1440855835 Sat Aug 29 21:43:55 2015
time of last status change:     1440855835 Sat Aug 29 21:43:55 2015
total size, in bytes:            236978176 (226.000 MiB)

Size to process:                 236978176 (226.000 MiB)
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         463312
time of last access:            1440825416 Sat Aug 29 13:16:56 2015
time of last modification:      1440855835 Sat Aug 29 21:43:55 2015
time of last status change:     1440855835 Sat Aug 29 21:43:55 2015
total size, in bytes:            236978176 (226.000 MiB)

Size to process:                 236978176 (226.000 MiB)
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         463312
time of last access:            1440855928 Sat Aug 29 21:45:28 2015
time of last modification:      1440855835 Sat Aug 29 21:43:55 2015
time of last status change:     1440855835 Sat Aug 29 21:43:55 2015
total size, in bytes:            236978176 (226.000 MiB)

Size to process:                 236978176 (226.000 MiB)
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         463312
time of last access:            1440855928 Sat Aug 29 21:45:28 2015
time of last modification:      1440855835 Sat Aug 29 21:43:55 2015
time of last status change:     1440855835 Sat Aug 29 21:43:55 2015
total size, in bytes:            236978176 (226.000 MiB)

Size to process:                 236978176 (226.000 MiB)
Worker(1): 56.64% done. 2015-08-29 21:45:30 ETA(in 00:00:01). Processing speed: 8.000 MiB/sec
Worker(0): 56.64% done. 2015-08-29 21:45:30 ETA(in 00:00:01). Processing speed: 8.000 MiB/sec
Worker(4): 56.64% done. 2015-08-29 21:45:30 ETA(in 00:00:01). Processing speed: 8.000 MiB/sec
Worker(3): 56.64% done. 2015-08-29 21:45:30 ETA(in 00:00:01). Processing speed: 8.000 MiB/sec
Worker(2): 56.64% done. 2015-08-29 21:45:30 ETA(in 00:00:01). Processing speed: 8.000 MiB/sec
Worker(7): 56.64% done. 2015-08-29 21:45:30 ETA(in 00:00:01). Processing speed: 8.000 MiB/sec
Worker(5): 56.64% done. 2015-08-29 21:45:30 ETA(in 00:00:01). Processing speed: 8.000 MiB/sec
Worker(6): 56.64% done. 2015-08-29 21:45:30 ETA(in 00:00:01). Processing speed: 8.000 MiB/sec
All workers finished in 1 sec

恢复mysql字典

[root@web103 mysql_recovery]# ./recover_dictionary.sh 
Generating dictionary tables dumps... OK
Creating test database ... OK
Creating dictionary tables in database test:
SYS_TABLES ... OK
SYS_COLUMNS ... OK
SYS_INDEXES ... OK
SYS_FIELDS ... OK
All OK
Loading dictionary tables data:
SYS_TABLES ... 162 recs OK
SYS_COLUMNS ... 1247 recs OK
SYS_INDEXES ... 216 recs OK
SYS_FIELDS ... 411 recs OK
All OK
[root@web103 mysql_recovery]# mysql test
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 10162
Server version: 5.0.95 Source distribution

Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> select * from SYS_TABLES WHERE name like 'recover%';
+-------------------------+-----+--------+------+--------+---------+--------------+-------+
| NAME                    | ID  | N_COLS | TYPE | MIX_ID | MIX_LEN | CLUSTER_NAME | SPACE |
+-------------------------+-----+--------+------+--------+---------+--------------+-------+
| recover/#sql-64a9_1f6d  | 120 |      8 |    1 |      0 |       0 |              |     0 | 
| recover/#sql2-64a9-1f6d | 115 |      8 |    1 |      0 |       0 |              |     0 | 
| recover/t_delete        |  74 |      2 |    1 |      0 |       0 |              |     0 | 
| recover/t_delete1       |  84 |      2 |    1 |      0 |       0 |              |     0 | 
| recover/t_drop          | 125 |      4 |    1 |      0 |       0 |              |     0 | 
| recover/t_truncate      | 120 |      8 |    1 |      0 |       0 |              |     0 | 
| recover/t_xifenfei      |  75 |      2 |    1 |      0 |       0 |              |     0 | 
| recover/zx_users        |  89 |     85 |    1 |      0 |       0 |              |     0 | 
+-------------------------+-----+--------+------+--------+---------+--------------+-------+
8 rows in set (0.00 sec)

mysql> select * from SYS_INDEXES WHERE TABLE_ID=125;
+----------+-----+---------+----------+------+-------+------------+
| TABLE_ID | ID  | NAME    | N_FIELDS | TYPE | SPACE | PAGE_NO    |
+----------+-----+---------+----------+------+-------+------------+
|      125 | 142 | PRIMARY |        1 |    3 |     0 | 4294967295 | 
+----------+-----+---------+----------+------+-------+------------+
1 row in set (0.00 sec)

恢复被删除表记录

[root@web103 mysql_recovery]# ./c_parser -5f pages-ibdata1/FIL_PAGE_INDEX/0000000000000142.page  -t dictionary/t_drop.sql >dumps/default/t_drop 2>2.sql
[root@web103 mysql_recovery]# more dumps/default/t_drop
-- Page id: 9860, Format: COMPACT, Records list: Valid, Expected records: (11 11)
00000099F9F2    80000026800110  t_drop  "10235259536125650"     "尊敬的用户您好:您的手机验证码为474851如非本人操作,请拨打奥斯卡客服:400-620-7575。"  "2010-01-01 00:00:00"   0
00000099F9F2    80000026800129  t_drop  "10235353811295807"     "尊敬的用户您好:您的手机验证码为444632如非本人操作,请拨打奥斯卡客服:400-620-7575。"  "2010-01-01 00:00:00"   0
00000099F9F2    80000026800142  t_drop  "102354211240398235"    "尊敬的用户您好:您的手机验证码为478503如非本人操作,请拨打奥斯卡客服:400-620-7575。"  "2010-01-01 00:00:00"   0
00000099F9F2    8000002680015C  t_drop  "102354554052884567"    "尊敬的用户您好:您的手机验证码为216825如非本人操作,请拨打奥斯卡客服:400-620-7575。"  "2010-01-01 00:00:00"   0
00000099F9F2    80000026800176  t_drop  "132213454294519126"    "尊敬的用户您好:您的手机验证码为854812如非本人操作,请拨打奥斯卡客服:400-620-7575。"  "2010-01-01 00:00:00"   0
00000099F9F2    80000026800190  t_drop  "82329022242584577"     "尊敬的用户您好:您的手机验证码为253127如非本人操作,请拨打奥斯卡客服:400-620-7575。"  "2010-01-01 00:00:00"   0
00000099F9F2    800000268001A9  t_drop  "82329022242584581"     "尊敬的用户您好:您的手机验证码为253127如非本人操作,请拨打奥斯卡客服:400-620-7575。"  "2010-01-01 00:00:00"   0
00000099F9F2    800000268001C2  t_drop  "8233400415607376"      "尊敬的用户您好:您的手机验证码为338470如非本人操作,请拨打奥斯卡客服:400-620-7575。"  "2010-01-01 00:00:00"   0
00000099F9F2    800000268001DA  t_drop  "82334502212106951"     "尊敬的用户您好:您的手机验证码为916515如非本人操作,请拨打奥斯卡客服:400-620-7575。"  "2010-01-01 00:00:00"   0
00000099F9F2    800000268001F3  t_drop  "82339012756833423"     "尊敬的用户您好:您的手机验证码为396108如非本人操作,请拨打奥斯卡客服:400-620-7575。"  "2010-01-01 00:00:00"   0
00000099F9F2    8000002680020C  t_drop  "8234322198577796"      "尊敬的用户您好:您的手机验证码为935297如非本人操作,请拨打奥斯卡客服:400-620-7575。"  "2010-01-01 00:00:00"   0
-- Page id: 9860, Found records: 11, Lost records: NO, Leaf page: YES

恢复数据入库

mysql> source dictionary/t_drop.sql
Query OK, 0 rows affected (0.00 sec)

mysql> source 2.sql
Query OK, 0 rows affected (0.00 sec)

Query OK, 11 rows affected (0.00 sec)
Records: 11  Deleted: 0  Skipped: 0  Warnings: 0

mysql> checksum table t_drop;
+-----------------+-----------+
| Table           | Checksum  |
+-----------------+-----------+
| recover.t_drop  | 920719058 | 
+-----------------+-----------+
1 row in set (0.00 sec)

至此实现删除数据完美恢复

mysql delete 恢复

在mysql(innodb引擎)中,有些时候犹豫误操作导致表中数据被删除,从而导致不可挽回的损失,本文模拟在数据库被误delete的情况下,实现较为完美删除,当然在实际中可能有少量不覆盖或者无法恢复回来,但是在覆盖不多或者未覆盖的情况下,可以实现绝大多数甚至全部恢复.因此在发生误操作时候,应当第一时间保护现场,尽可能防止复写导致不可挽回的损失.在测试恢复过程中,由于mysql和操作系统编码问题,折腾了很久,感谢Lunar的指点
创建模拟表并插入数据

mysql> CREATE TABLE `sms_send_record_del` (
    ->   `messageId` varchar(30) NOT NULL,
    ->   `tokenId` varchar(20) NOT NULL,
    ->   `mobile` varchar(14) default NULL,
    ->   `msgFormat` int(1) NOT NULL,
    ->   `msgContent` varchar(1000) default NULL,
    ->   `scheduleDate` timestamp NOT NULL default CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
    ->   `deliverState` int(1) default NULL,
    ->   `deliverdTime` timestamp NOT NULL default '0000-00-00 00:00:00',
    ->   PRIMARY KEY  (`messageId`)
    -> ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
Query OK, 0 rows affected (0.00 sec)

mysql> insert into sms_send_record_del select * from sms_send_record;
Query OK, 11 rows affected (0.00 sec)
Records: 11  Duplicates: 0  Warnings: 0

mysql> checksum table sms_send_record_del;
+---------------------------------+------------+
| Table                           | Checksum   |
+---------------------------------+------------+
| sms_service.sms_send_record_del | 2258631583 | 
+---------------------------------+------------+
1 row in set (0.00 sec)

mysql> checksum table sms_send_record;    
+-----------------------------+------------+
| Table                       | Checksum   |
+-----------------------------+------------+
| sms_service.sms_send_record | 2258631583 | 
+-----------------------------+------------+
1 row in set (0.00 sec)

mysql-delete-recovery-1


确定innodb文件对应位置

mysql> SHOW VARIABLES LIKE 'datadir';
+---------------+-----------------+
| Variable_name | Value           |
+---------------+-----------------+
| datadir       | /var/lib/mysql/ | 
+---------------+-----------------+
1 row in set (0.00 sec)

mysql> SHOW VARIABLES LIKE 'innodb_file_per_table';
+-----------------------+-------+
| Variable_name         | Value |
+-----------------------+-------+
| innodb_file_per_table | OFF   | 
+-----------------------+-------+
1 row in set (0.00 sec)

mysql> SHOW VARIABLES LIKE 'innodb_data_file_path';
+-----------------------+------------------------+
| Variable_name         | Value                  |
+-----------------------+------------------------+
| innodb_data_file_path | ibdata1:10M:autoextend | 
+-----------------------+------------------------+
1 row in set (0.00 sec)

删除表记录
模拟错误操作,误删除表所有数据

mysql> delete from sms_send_record_del;
Query OK, 11 rows affected (0.00 sec)

解析ibdata1文件

[root@web103 mysql_recovery]# ./stream_parser -f /var/lib/mysql/ibdata1 
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         315712
time of last access:            1440599559 Wed Aug 26 22:32:39 2015
time of last modification:      1440601853 Wed Aug 26 23:10:53 2015
time of last status change:     1440601853 Wed Aug 26 23:10:53 2015
total size, in bytes:            161480704 (154.000 MiB)

Size to process:                 161480704 (154.000 MiB)
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         315712
time of last access:            1440599559 Wed Aug 26 22:32:39 2015
time of last modification:      1440601853 Wed Aug 26 23:10:53 2015
time of last status change:     1440601853 Wed Aug 26 23:10:53 2015
total size, in bytes:            161480704 (154.000 MiB)

Size to process:                 161480704 (154.000 MiB)
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         315712
time of last access:            1440599559 Wed Aug 26 22:32:39 2015
time of last modification:      1440601853 Wed Aug 26 23:10:53 2015
time of last status change:     1440601853 Wed Aug 26 23:10:53 2015
total size, in bytes:            161480704 (154.000 MiB)

Size to process:                 161480704 (154.000 MiB)
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         315712
time of last access:            1440599559 Wed Aug 26 22:32:39 2015
time of last modification:      1440601853 Wed Aug 26 23:10:53 2015
time of last status change:     1440601853 Wed Aug 26 23:10:53 2015
total size, in bytes:            161480704 (154.000 MiB)

Size to process:                 161480704 (154.000 MiB)
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         315712
Opening file: /var/lib/mysql/ibdata1
time of last access:            1440599559 Wed Aug 26 22:32:39 2015
time of last modification:      1440601853 Wed Aug 26 23:10:53 2015
time of last status change:     1440601853 Wed Aug 26 23:10:53 2015
File information:

total size, in bytes:            161480704 (154.000 MiB)

ID of device containing file:         2049
Size to process:                 161480704 (154.000 MiB)
Opening file: /var/lib/mysql/ibdata1
File information:

ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         315712
time of last access:            1440599559 Wed Aug 26 22:32:39 2015
time of last modification:      1440601853 Wed Aug 26 23:10:53 2015
time of last status change:     1440601853 Wed Aug 26 23:10:53 2015
total size, in bytes:            161480704 (154.000 MiB)

Size to process:                 161480704 (154.000 MiB)
Opening file: /var/lib/mysql/ibdata1
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
File information:

blocksize for filesystem I/O:         4096
number of blocks allocated:         315712
ID of device containing file:         2049
inode number:                      1344553
protection:                         100660 (regular file)
number of hard links:                    1
user ID of owner:                       27
group ID of owner:                      27
device ID (if special file):             0
blocksize for filesystem I/O:         4096
number of blocks allocated:         315712
time of last access:            1440599559 Wed Aug 26 22:32:39 2015
time of last modification:      1440601853 Wed Aug 26 23:10:53 2015
time of last status change:     1440601853 Wed Aug 26 23:10:53 2015
total size, in bytes:            161480704 (154.000 MiB)

Size to process:                 161480704 (154.000 MiB)
time of last access:            1440601884 Wed Aug 26 23:11:24 2015
time of last modification:      1440601853 Wed Aug 26 23:10:53 2015
time of last status change:     1440601853 Wed Aug 26 23:10:53 2015
total size, in bytes:            161480704 (154.000 MiB)

Size to process:                 161480704 (154.000 MiB)
All workers finished in 0 sec

分析数据字典

mysql> show tables
    -> ;
+----------------+
| Tables_in_test |
+----------------+
| SYS_COLUMNS    | 
| SYS_FIELDS     | 
| SYS_INDEXES    | 
| SYS_TABLES     | 
+----------------+
4 rows in set (0.00 sec)

mysql> select * from SYS_TABLES;
+----------------------------------------+----+-------------+------+--------+---------+--------------+-------+
| NAME                                   | ID | N_COLS      | TYPE | MIX_ID | MIX_LEN | CLUSTER_NAME | SPACE |
+----------------------------------------+----+-------------+------+--------+---------+--------------+-------+
| recover/t_delete                       | 74 |           2 |    1 |      0 |       0 |              |     0 | 
| recover/t_delete1                      | 84 |           2 |    1 |      0 |       0 |              |     0 | 
| recover/t_xifenfei                     | 75 |           2 |    1 |      0 |       0 |              |     0 | 
| recover/zx_users                       | 89 |          85 |    1 |      0 |       0 |              |     0 | 
| sms_service/sms_send_record            | 36 |           8 |    1 |      0 |       0 |              |     0 | 
| sms_service/sms_send_record_del        | 90 |           8 |    1 |      0 |       0 |              |     0 | 
| SYS_FOREIGN                            | 11 | -2147483644 |    1 |      0 |       0 |              |     0 | 
| SYS_FOREIGN_COLS                       | 12 | -2147483644 |    1 |      0 |       0 |              |     0 | 
| test/SYS_COLUMNS                       | 86 |           7 |    1 |      0 |       0 |              |     0 | 
| test/SYS_FIELDS                        | 88 |           3 |    1 |      0 |       0 |              |     0 | 
| test/SYS_INDEXES                       | 87 |           7 |    1 |      0 |       0 |              |     0 | 
| test/SYS_TABLES                        | 85 |           8 |    1 |      0 |       0 |              |     0 | 
| test/zx_users                          | 43 |          85 |    1 |      0 |       0 |              |     0 | 
| xifenfei/t_delete                      | 44 |           8 |    1 |      0 |       0 |              |     0 | 
| xifenfei/t_xifenfei                    | 59 |           2 |    1 |      0 |       0 |              |     0 | 
+----------------------------------------+----+-------------+------+--------+---------+--------------+-------+
39 rows in set (0.00 sec)

mysql> select * from SYS_INDEXES WHERE TABLE_ID=90;
+----------+-----+---------+----------+------+-------+---------+
| TABLE_ID | ID  | NAME    | N_FIELDS | TYPE | SPACE | PAGE_NO |
+----------+-----+---------+----------+------+-------+---------+
|       90 | 110 | PRIMARY |        1 |    3 |     0 |    2955 | 
+----------+-----+---------+----------+------+-------+---------+
1 row in set (0.00 sec)

找回被删除记录

[root@web103 mysql_recovery]# ./c_parser -5Df pages-ibdata1/FIL_PAGE_INDEX/0000000000000110.page \
[root@web103 mysql_recovery]#    -t dictionary/sms_send_record_del.sql >/tmp/t_1.txt 2>/tmp/t_1.sql

mysql-delete-recovery-2


加载数据并验证

mysql> use sms_service;
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> source /tmp/t_1.sql
Query OK, 0 rows affected (0.00 sec)

Query OK, 11 rows affected, 8 warnings (0.01 sec)
Records: 11  Deleted: 0  Skipped: 0  Warnings: 8

mysql> checksum table sms_send_record_del;
+---------------------------------+------------+
| Table                           | Checksum   |
+---------------------------------+------------+
| sms_service.sms_send_record_del | 2258631583 | 
+---------------------------------+------------+
1 row in set (0.00 sec)

发生误操作之时,请尽可能保护现场,防止覆盖导致无可挽回的损失.

mysql数据字典恢复

在以前的文章中说过mysql的数据字典的恢复(使用工具直接抽取MySQL数据字典,缺少SYS_FIELDS表),主要的数据字典有一下几个,在本文中主要对这些数据字典的意义进行一些讲解,为大家更深一步了解mysql恢复处理思路
MySQL恢复字典表

mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| SYS_COLUMNS    | 
| SYS_FIELDS     | 
| SYS_INDEXES    | 
| SYS_TABLES     | 
+----------------+
4 rows in set (0.00 sec)

SYS_TABLES
这个表是mysql恢复的最核心的表之一,主要是记录数据库在InnoDB中表的信息。它默认写在InnoDB的index_ids为1的里面,它的根页在8号page上,他的主要列结构为:

mysql> desc SYS_TABLES;
+--------------+---------------------+------+-----+---------+-------+
| Field        | Type                | Null | Key | Default | Extra |
+--------------+---------------------+------+-----+---------+-------+
| NAME         | varchar(255)        | NO   | PRI |         |       | 
| ID           | bigint(20) unsigned | NO   |     | 0       |       | 
| N_COLS       | int(10)             | YES  |     | NULL    |       | 
| TYPE         | int(10) unsigned    | YES  |     | NULL    |       | 
| MIX_ID       | bigint(20) unsigned | YES  |     | NULL    |       | 
| MIX_LEN      | int(10) unsigned    | YES  |     | NULL    |       | 
| CLUSTER_NAME | varchar(255)        | YES  |     | NULL    |       | 
| SPACE        | int(10) unsigned    | YES  |     | NULL    |       | 
+--------------+---------------------+------+-----+---------+-------+
8 rows in set (0.00 sec)

NAME:顾名思义,就是表的名字,但是注意他记录的格式是db/table,例如:xifenfei/zx_users,表示为xifenfei数据库中的zx_users表
ID:表的编号
N_COLS:表一共包含的列的数量
TYPE, MIX_ID, MIX_LEN 和 CLUSTER_NAME列,对于数据库恢复无任何意义不做描述
SPACE:表空间的标示列. 例如: ibdata1 是 SPACE 0, ibdata2 是 SPACE 1, 每一个 ibd 文件都有自己的表空间标示.

SYS_INDEXES
这个也是mysql恢复的最核心表之一,主要是记录InnoDB的index信息,它默认InnoDB的index_ids为3的里面,他的主要结构为:

mysql> desc SYS_INDEXES;
+----------+---------------------+------+-----+---------+-------+
| Field    | Type                | Null | Key | Default | Extra |
+----------+---------------------+------+-----+---------+-------+
| TABLE_ID | bigint(20) unsigned | NO   | PRI | 0       |       | 
| ID       | bigint(20) unsigned | NO   | PRI | 0       |       | 
| NAME     | varchar(120)        | YES  |     | NULL    |       | 
| N_FIELDS | int(10) unsigned    | YES  |     | NULL    |       | 
| TYPE     | int(10) unsigned    | YES  |     | NULL    |       | 
| SPACE    | int(10) unsigned    | YES  |     | NULL    |       | 
| PAGE_NO  | int(10) unsigned    | YES  |     | NULL    |       | 
+----------+---------------------+------+-----+---------+-------+
7 rows in set (0.00 sec)

TABLE_ID:表标示列,为SYS_TABLES.ID
ID:为InnoDB中的index的编号,这个在恢复中非常重要,恢复之时需要根据这个去定位具体的文件
NAME:主要表的index的名字,有PRIMARY 和 普通列的index信息,一般恢复之时我们选择PRIMARY
N_FIELDS:表名index包含列的数量,在mysql恢复中不重要
TYPE:恢复之中使用不到该列,不做说明
PAGE:用途等同SYS_TABLES.SPACE
PAGE_NO:标示为每个index的root page的page号,关于index中的page结构如下图所示
Bplustree


SYS_COLUMNS
这个表主要记录数据库中表的列的情况,它存储在index_id 2中.主要用它来确定需要恢复表的列的情况,如果你知道完全的列结构,该表不是MySQL恢复所必须的,它的主要结构为:

mysql> desc SYS_COLUMNS;
+----------+---------------------+------+-----+---------+-------+
| Field    | Type                | Null | Key | Default | Extra |
+----------+---------------------+------+-----+---------+-------+
| TABLE_ID | bigint(20) unsigned | NO   | PRI | NULL    |       | 
| POS      | int(10) unsigned    | NO   | PRI | NULL    |       | 
| NAME     | varchar(255)        | YES  |     | NULL    |       | 
| MTYPE    | int(10) unsigned    | YES  |     | NULL    |       | 
| PRTYPE   | int(10) unsigned    | YES  |     | NULL    |       | 
| LEN      | int(10) unsigned    | YES  |     | NULL    |       | 
| PREC     | int(10) unsigned    | YES  |     | NULL    |       | 
+----------+---------------------+------+-----+---------+-------+
7 rows in set (0.00 sec)

TABLE_ID:表标示列,为SYS_TABLES.ID
POS:该列所在表中的位置,该值从0开始
NAME:列的名字
MTYPE 和 PRTYPE:主要是为了记录列的类型,出现此类问题主要是由于InnoDB最初并不是为MySQL而设计,到了后面为更好支持MySQL,因此出现了两种情况.
LEN:列的长度.这个需要注意编码,比如数据库是utf8编码,定义的varchar(10),实际该处长度显示为30,因为每个除英文外的字符编码为3个byte.
PREC:有些特殊类型中,列的精确度定义

SYS_FIELDS
记录所有index的列的分布信息,它存储在index_id 4中,该表不是MySQL恢复所必须的,它的主要结构为:

mysql> desc SYS_FIELDS;
+----------+---------------------+------+-----+---------+-------+
| Field    | Type                | Null | Key | Default | Extra |
+----------+---------------------+------+-----+---------+-------+
| INDEX_ID | bigint(20) unsigned | NO   | PRI | NULL    |       | 
| POS      | int(10) unsigned    | NO   | PRI | NULL    |       | 
| COL_NAME | varchar(255)        | YES  |     | NULL    |       | 
+----------+---------------------+------+-----+---------+-------+
3 rows in set (0.00 sec)

INDEX_ID:index的标志,等同SYS_INDEXES.ID
POS:列在index中的位置,从0开始
COL_NAME:列的名称
通过上述相关表和列,然后结合MySQL相关恢复工具,就可以从底层在InnoDB出现问题,或者误操作之时提供恢复处理.

Mysql查询视图:ERROR 1449 (HY000)

1、问题重现
前几天因为有人删除了数据库中的记录,今天关闭了数据库的远程访问功能,今天接到开发报告,说出现 The user specified as a definer (‘air’@’%’) does not exist错误,他们定位是一张视图不能访问。利用实验重现了他们的情况

[root@ECP-UC-DB1 ~]# mysql -uxff -pxifenfei
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 8846
Server version: 5.5.14-log MySQL Community Server (GPL)

Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> select user,host from mysql.user;
+------+---------------+
| user | host          |
+------+---------------+
| xff  | %             |
| root | 127.0.0.1     |
| repl | 192.168.11.10 |
| root | ::1           |
|      | ECP-UC-DB1    |
| root | ECP-UC-DB1    |
| root | localhost     |
+------+---------------+
7 rows in set (0.08 sec)

mysql> use xifenfei;
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> create view v_users as select * from wp_users;
Query OK, 0 rows affected (0.14 sec)

mysql> select count(*) from xifenfei.v_users;
+----------+
| count(*) |
+----------+
|        2 |
+----------+
1 row in set (0.03 sec)

mysql> update mysql.user set host='localhost' where user='xff' and host='%';
Query OK, 1 row affected (0.05 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> FLUSH PRIVILEGES;                   
Query OK, 0 rows affected (0.12 sec)

mysql> exit
Bye
[root@ECP-UC-DB1 ~]# mysql -uxff -pxifenfei
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 8847
Server version: 5.5.14-log MySQL Community Server (GPL)

Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> use xff;
ERROR 1049 (42000): Unknown database 'xff'
mysql> use xifenfei;
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 v_users ;
ERROR 1449 (HY000): The user specified as a definer ('xff'@'%') does not exist

2、解决方法

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
| xifenfei           |
+--------------------+
5 rows in set (0.00 sec)

mysql> use information_schema;
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> desc VIEWS;
+----------------------+--------------+------+-----+---------+-------+
| Field                | Type         | Null | Key | Default | Extra |
+----------------------+--------------+------+-----+---------+-------+
| TABLE_CATALOG        | varchar(512) | NO   |     |         |       |
| TABLE_SCHEMA         | varchar(64)  | NO   |     |         |       |
| TABLE_NAME           | varchar(64)  | NO   |     |         |       |
| VIEW_DEFINITION      | longtext     | NO   |     | NULL    |       |
| CHECK_OPTION         | varchar(8)   | NO   |     |         |       |
| IS_UPDATABLE         | varchar(3)   | NO   |     |         |       |
| DEFINER              | varchar(77)  | NO   |     |         |       |
| SECURITY_TYPE        | varchar(7)   | NO   |     |         |       |
| CHARACTER_SET_CLIENT | varchar(32)  | NO   |     |         |       |
| COLLATION_CONNECTION | varchar(32)  | NO   |     |         |       |
+----------------------+--------------+------+-----+---------+-------+
10 rows in set (0.02 sec)

mysql> select TABLE_SCHEMA,TABLE_NAME,DEFINER from views;
+--------------+------------+---------+
| TABLE_SCHEMA | TABLE_NAME | DEFINER |
+--------------+------------+---------+
| xifenfei     | v_users    | xff@%   |
+--------------+------------+---------+
1 row in set (0.16 sec)

mysql> create or replace view v_users as select * from wp_users;
ERROR 1044 (42000): Access denied for user 'xff'@'localhost' to database 'information_schema'
mysql> create or replace view xifenfei.v_users as select * from xifenfei.wp_users;
Query OK, 0 rows affected (0.02 sec)

mysql> select TABLE_SCHEMA,TABLE_NAME,DEFINER from views;
+--------------+------------+---------------+
| TABLE_SCHEMA | TABLE_NAME | DEFINER       |
+--------------+------------+---------------+
| xifenfei     | v_users    | xff@localhost |
+--------------+------------+---------------+
1 row in set (0.01 sec)

mysql> select count(*) from xifenfei.v_users;
+----------+
| count(*) |
+----------+
|        2 |
+----------+
1 row in set (0.03 sec)

3、原因分析
因为创建视图使用的是xff@%用户(目前已经不存在),然后登录用户使用的是xff@localhost用户,导致mysql认为现在的用户无权限访问该视图,解决方法就是在当前用户下重建该视图