CREATE OR REPLACE FUNCTION "agis"."select_preview_map" () RETURNS SETOF record AS
$body$
SELECT
  Force_2d(O.object_geometry) AS plgn,
  O.object_type AS object_type,
  CASE WHEN B.building_part = TRUE
       THEN O.parent_guid 
       ELSE O.guid END AS root_guid  
FROM
  object O,
  building B
WHERE
  O.guid = B.object_guid 
  AND O.object_geometry IS NOT NULL

UNION ALL

SELECT
  Force_2d(O.object_geometry) AS plgn,
  O.object_type AS object_type,
  O.guid AS root_guid  
FROM
  object O,
  water_body B,
  landmark L
WHERE
  (O.guid = B.object_guid
  OR O.guid = L.object_guid) 
  AND O.object_geometry IS NOT NULL

ORDER BY
  root_guid;
$body$
LANGUAGE 'sql' VOLATILE CALLED ON NULL INPUT SECURITY INVOKER;