Fatal error: SQL ERROR [ mysql4 ]

Incorrect key file for table '/tmp/#sql_2251_0.MYI'; try to repair it

CALLING PAGE

/index.php&

SQL

SELECT DISTINCT SQL_CALC_FOUND_ROWS B.*, U.username FROM sc_users AS U, sc_bookmarks AS B WHERE B.uId = U.uId AND B.bStatus = 0 AND B.bDatetime > "-0722-08-31 00:00:00" AND B.bDatetime < "2016-07-27 00:00:00" ORDER BY B.bDatetime DESC LIMIT 20
in /var/www/clients/client2/web25/web/includes/db/mysql4.php on line 390