phpBB : Critical Error

Error doing DB query userdata row fetch

DEBUG MODE

SQL Error : 145 Table './myforum/phpbb_sessions' is marked as crashed and should be repaired

SELECT u.*, s.* FROM phpbb_sessions s, phpbb_users u WHERE s.session_id = '7734438bdfd8da3c7d3fbd41039cd143' AND u.user_id = s.session_user_id

Line : 315
File : sessions.php