subject: Power Surge Causes Improper Shutdown And Corruption To Mysql Database [print this page] MySQL is a widely-used and advanced relational database management system. It enables you to store your significant data in a reliable database, using either InnoDB or MyISAM storage engines. You can also use MySQL database with any of the project management tools to effectively manage and use your database. However, in some situations, you may come across serious MySQL database corruption, if power failure occurs while using your database with a project management tool. This behavior prevents you to access your valuable data and leads to critical data loss situations. In such critical circumstances, you need to repair MySQL database if there is no valid backup in place.
After improper system shutdown, your InnoDB database of MySQL cannot be opened and accessed. The service fails to start every time. Even the "innodb_force_recovery" fails to fix the problem. The situations may become more critical if you do not have complete backup of the database. In such situations, the following error message appears in the error log of MySQL:
"InnoDB: The log sequence number in ibdata files does not match
InnoDB: the log sequence number in the ib_logfiles!
100308 14:50:01 InnoDB: Database was not shut down normally!
InnoDB: Starting crash recovery.
InnoDB: Reading tablespace information from the .ibd files...
InnoDB: Restoring possible half-written data pages from the doublewrite
InnoDB: Your database may be corrupt or you may have copied the InnoDB
InnoDB: tablespace but not the InnoDB log files."
As stated in the above error, the MySQL recovery process fails and database remains unusable.
Cause
The problem generally occurs due to corruption to MySQL database after improper system shutdown. In such cases, MySQL application can not read the database and since the corruption is serious, it ca not even
recover the database.
Solution
You can fix the problem by restoring MySQL database from current backup. In case the backup is not available, you have to repair mysql atabase tables using third-party applications.
The MySQL repair software are powerful enough to thoroughly scan entire database and extract all inaccessible data from it. They have simple user interface and non-destructive conduct to offer easy and secure recovery.
Database Recovery for MySQL software repairs and restores corrupt MySQL database in a quick and absolute way. The mysql repair software works well with
MySQL 5.x and 4.x. It supports both InnoDB and MyISAM storage engines of MySQL.