Sometimes a MySQL utility will report an error such as:
Got error: 145: Table '<tablename>' is marked as crashed and should be repaired when using LOCK TABLES
You can check the index files using the myisamchk utility,
cd /var/lib/mysql/<dbname>
myisamchk -e *.MYI
which should show an output similar to:
Checking MyISAM file: <tablename>.MYI
Data records: 130 Deleted blocks: 0
myisamchk: warning: Table is marked as crashed
- check file-size
- check record delete-chain
- check key delete-chain
- check index reference
- check data record references index: 1
- check data record references index: 2
- check data record references index: 3
- check records and index references
MyISAM-table '<tablename>.MYI' is usable but should be fixed
In this case, the table is fine, but just marked as crashed. Make sure the MySQL server is stopped
/etc/init.d/mysql stop
and then use myisamchk to mark the table is ok.
myisamchk --update-state <tablename>.MYI
You can then restart MySQL
/etc/init.d/mysql start
If the index file is actually corrupt, but the data is ok, the index file can be rebuilt:
myisamchk -r -q <tablename>
Full details are available on the MySQL website: 5.6.3. How to Repair MyISAM Tables