SELECT 
      st_astext(ST_PointOnSurface(ST_Buffer(z.geom,0.1))) as geom, 
      z.zonelib as titre,  
      c.cimetierelib||' '||zt.libelle||' '||z.zonelib||' ('||z.zone||')' as description, 
      z.zone as idx
from &DB_PREFIXEzone z 
JOIN &DB_PREFIXEcimetiere c 
      ON c.cimetiere=z.cimetiere 
JOIN &DB_PREFIXEzone_type zt 
      ON zt.zone_type=z.zonetype 
WHERE 
       z.cimetiere IN (SELECT distinct cimetiere FROM  &DB_PREFIXEzone WHERE zone IN (&idx))