select lender_libelle as Propriétaire, location_libelle as Localisation, statut_libelle as Statut, count(*) as Nombre from exemplaires, lenders, docs_location, docs_statut where expl_owner=idlender and idlocation=expl_location and idstatut=expl_statut group by lender_libelle,location_libelle,statut_libelle order by 1,2,3