phpBB : Critical Error

Error doing DB query userdata row fetch

DEBUG MODE

SQL Error : 2013 Lost connection to MySQL server during query

SELECT u.*, s.* FROM blitz_sessions s, blitz_users u WHERE s.session_id = '2cb146fcf8761ff5c13206ef990024e6' AND u.user_id = s.session_user_id

Line : 331
File : sessions.php