SELECT
 (T_SAL.MatriculeSalarie || ' ' || NVL(T_SAL.Nom, ' ') || ' '  || NVL(T_SAL.Prenom, ' ') ) as Col1,
 'Dernière visite médicale : ' || NVL(TO_CHAR(T_HST_MEDECINE.DateVisite), 'vide') as Col2
FROM
  T_PAI,
  T_SAL
  LEFT OUTER JOIN T_HST_MEDECINE ON T_HST_MEDECINE.NumSalarie=T_SAL.SA_CompteurNumero
                  AND T_HST_MEDECINE.InfoEnCours=1
Where ((T_HST_MEDECINE.DateVisite is null)
  OR  (extract(MONTH FROM Add_months(T_HST_MEDECINE.DateVisite, NVL(%visitesMedicales%,0))) = T_PAI.MoisEnCours
      AND extract(YEAR FROM Add_months(T_HST_MEDECINE.DateVisite, NVL(%visitesMedicales%,0))) = T_PAI.AnneeEnCours))

Order By T_SAL.MatriculeSalarie