SELECT expl_id as object_id, 'EXPL' as object_type, concat("LIVRE ",tit1) as Titre FROM notices join exemplaires on expl_notice=notice_id LEFT JOIN pret_archive ON arc_expl_notice = notice_id where arc_expl_id IS NULL AND expl_id IS NOT NULL UNION SELECT expl_id as object_id, 'EXPL' as object_type, concat("PERIO ",tit1, " Numéro : ",bulletin_numero) as Titre FROM (bulletins INNER JOIN notices ON bulletins.bulletin_notice = notices.notice_id) INNER JOIN exemplaires on expl_bulletin=bulletin_id LEFT JOIN pret_archive ON expl_id = arc_expl_id WHERE pret_archive.arc_id Is Null