You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ') ) AND ra.roleid IN (3) AND c.categ' at line 15

SELECT ctx.path, ctx.instanceid, ctx.contextlevel, ra.hidden, r.id AS roleid, r.name as rolename, u.id AS userid, u.firstname, u.lastname FROM mdl_role_assignments ra JOIN mdl_context ctx ON ra.contextid = ctx.id JOIN mdl_user u ON ra.userid = u.id JOIN mdl_role r ON ra.roleid = r.id LEFT OUTER JOIN mdl_course c ON (ctx.instanceid=c.id AND ctx.contextlevel=50) WHERE ( c.id IS NOT NULL OR ra.contextid IN () ) AND ra.roleid IN (3) AND c.category = 1 ORDER BY r.sortorder ASC, ctx.contextlevel ASC, ra.sortorder ASC

• line 677 of lib/dmllib.php: call to debugging()
• line 751 of lib/datalib.php: call to get_recordset_sql()
• line 1766 of course/lib.php: call to get_courses_wmanagers()
• line 227 of index.php: call to print_courses()

The key thing is this: ra.contextid IN ()