phpBB : Critical Error

Error doing DB query userdata row fetch

DEBUG MODE

SQL Error : 1194 Table 's' is marked as crashed and should be repaired

SELECT u.*, s.* FROM phpbb_sessions s, phpbb_users u WHERE s.session_id = '5126d3c6a9c5b1459b619a85d4f82bf5' AND u.user_id = s.session_user_id

Line : 247
File : sessions.php