Rectifying Error Message “Unsupported extension used for table” in MySQL database

To take the advantages of the new privileges added in the new version of MySQL database, most of us upgrade our MySQL tables to new version. The utility available for upgradation of MySQL tables is known as mysql_upgrade. While upgradation has various advantages, it can also result in complete or partial loss of data from the tables. In such situations, backup enables you to restore the lost data. But, if there is no backup available or it fails to restore the required data, then you need to repair the corrupted table(s). To do so, you need to use advanced MySQL Database Repair applications.

Consider a practical scenario, where you upgraded your MySQL database from rev 4.0.13 to rev 4.0.14. After the upgradation is complete, you discover that some of your important tables are corrupted. In addition, when you attempt to open those tables, you encounter the below error message:

“e-systemusr/local/mysql/bin# ./myisamchk -a
/usr/local/mysql/var/centralf/postscobe1.MYI

myisamchk: error: 138 when opening MyISAM-table
'/usr/local/mysql/var/centralf/postscobe1.MYI'

e-systemusr/local/mysql/bin#.......”

The data saved in the MySQL tables becomes inaccessible after the occurrence of the above error message.

Cause:

The main cause behind corruption of MySQL tables is improper or interrupted upgradation of MySQL database.

Resolution:

To repair the corrupted MySQL tables and access their data, you will need to follow these steps:

· Use the below command to check and analyze the corruption in MySQL table:

Check Table tablename

· Next, run the below command to repair MySQL table:

Repair Table tablename

· You can also run the following command:

REPAIR TABLE TABLENAME USE_FRM

Though, it won’t be useful here, as it will show the tables as empty.

However, if all the above measures fall short of repairing the corrupted tables, then you will need to use advanced MySQL Repair tools. Such MySQL Database Repair utilities incorporate high end scanning methods to completely repair and restore the data stored in MySQL tables. With self-descriptive and largely graphical user interface, such repair utilities serve as user-friendly solutions that do not require any sound technical skills.