如何恢复崩溃的无害数据库.？

Question

我有一个Innodb表，我得到的错误是

mysql> check table City;
+-------------------+-------+----------+----------------------------------------------------------+
| Table             | Op    | Msg_type | Msg_text                                                 |
+-------------------+-------+----------+----------------------------------------------------------+
| world_innodb.City | check | Error    | Incorrect information in file: './world_innodb/City.frm' |
| world_innodb.City | check | error    | Corrupt                                                  |
+-------------------+-------+----------+----------------------------------------------------------+
2 rows in set (0.00 sec)

我没有改变任何东西。我不知道它是怎么坠毁的。我怎么能找回它..。

错误日志的内容如下

120207 11:50:47 InnoDB: highest supported file format is Barracuda.
120207 11:50:47  InnoDB: Waiting for the background threads to start
120207 11:50:48 InnoDB: 1.1.8 started; log sequence number 5713326
120207 11:50:48 [Note] Event Scheduler: Loaded 0 events
120207 11:50:48 [Note] /usr/local/mysql/bin/mysqld: ready for connections.
Version: '5.5.20-log'  socket: '/tmp/mysql.sock'  port: 3306  MySQL Community Server (GPL)
120207 11:50:57 [ERROR] /usr/local/mysql/bin/mysqld: Incorrect information in file: './world_innodb/City.frm'

编辑

有人打开了City.frm文件并修改了它的content.So，我将如何恢复它。我正在使用innodb_file_per_table。

更新:按照某些人的要求添加my.cnf。

Innodb在My.Cnf

中的特定变量

innodb_file_per_table
innodb_data_home_dir            = /usr/local/mysql/data
innodb_data_file_path           = ibdata1:10M:autoextend
innodb_log_group_home_dir       = /usr/local/mysql/data
innodb_buffer_pool_size         = 1G
innodb_additional_mem_pool_size = 2M
innodb_log_file_size            = 128M
innodb_log_files_in_group       = 2
innodb_log_buffer_size          = 8M
innodb_flush_log_at_trx_commit  = 1
innodb_lock_wait_timeout        = 50
innodb_force_recovery           = 4 

Answer 1

我创建了一个名为test2的表

CREATE TABLE `test2` (   `t` int(11) DEFAULT NULL ) ENGINE=InnoDB DEFAULT CHARSET=latin1;

然后我插入了一张唱片

insert into test2 values(1);

我停止了MySQL，然后用vi将一堆字符添加到test2.frm文件中。

然后我启动了MySQL，并看到了以下内容

mysql> show table status \G;
*************************** 1. row ***************************
           Name: test2
         Engine: NULL
        Version: NULL
     Row_format: NULL
           Rows: NULL
 Avg_row_length: NULL
    Data_length: NULL
Max_data_length: NULL
   Index_length: NULL
      Data_free: NULL
 Auto_increment: NULL
    Create_time: NULL
    Update_time: NULL
     Check_time: NULL
      Collation: NULL
       Checksum: NULL
 Create_options: NULL
        Comment: Incorrect information in file: './test2/test2.frm'

然后我创建了另一个具有相同结构的表。

CREATE TABLE `test3` (   `t` int(11) DEFAULT NULL ) ENGINE=InnoDB DEFAULT CHARSET=latin1;

然后我停止了mysql并在test2.frm上复制了test3.frm

cp /var/lib/mysql/testdb/test3.frm /var/lib/mysql/testdb/test2.frm

我重新启动了MySQL并访问了test2

mysql> show table status \G;
*************************** 1. row ***************************
           Name: test2
         Engine: InnoDB
        Version: 10
     Row_format: Compact
           Rows: 1
 Avg_row_length: 16384
    Data_length: 16384
Max_data_length: 0
   Index_length: 0
      Data_free: 25675431936
 Auto_increment: NULL
    Create_time: 2012-02-07 16:24:20
    Update_time: NULL
     Check_time: NULL
      Collation: latin1_swedish_ci
       Checksum: NULL
 Create_options: 
        Comment: 

这是我插入的记录

mysql> select * from test2;
+------+
| t    |
+------+
|    1 |
+------+
1 row in set (0.00 sec)

如果您知道表城市的结构，您可以创建一个相同的表，然后在现有的损坏表上复制.frm文件