CREATE OR REPLACE TRIGGER TRIG_EMPLEADOS
BEFORE INSERT OR UPDATE ON N_EMPLEADOS
FOR EACH ROW WHEN
    (NEW.FECHA_ALTA > SYSDATE)
    (UPPER.NEW.SEXO <> 'H' OR UPPER.NEW.SEXO <> 'M')


BEGIN
    RAISE_APLICATION_ERROR(-20001, 'HA OCURRIDO UN ERROR')

END;