Неверный запрос: select distinct (themes.THID) , themes.* from themes left join permissions on (themes.PID=permissions.PID) left join group_members on (group_members.UID='0') where ( ( (permissions.Editors=group_members.GID and permissions.Editors!=0) or (permissions.Users=group_members.GID and permissions.Users!=0) ) or (group_members.GID=3) or (themes.PID=permissions.PID and permissions.Guestable=1) ) and themes.DC LIKE '2017%' ORDER BY themes.DC DESC LIMIT -25,25