No render_height attributes on z13

layers/building/building.sql

@@ -1,22 +1,23 @@
-
-
-
--- etldoc: layer_building[shape=record fillcolor=lightpink, style="rounded,filled",  
+-- etldoc: layer_building[shape=record fillcolor=lightpink, style="rounded,filled",
 -- etldoc:     label="layer_building | <z13> z13 | <z14_> z14_ " ] ;
 
 CREATE OR REPLACE FUNCTION layer_building(bbox geometry, zoom_level int)
 RETURNS TABLE(geom geometry, osm_id bigint, render_height int, render_min_height int) AS $$
-    SELECT geometry, osm_id,
-    greatest(5, COALESCE(height, levels*3.66,5))::int AS render_height,
-    greatest(0, COALESCE(min_height, min_level*3.66,0))::int AS render_min_height
+    SELECT geometry, osm_id, render_height, render_min_height
     FROM (
-
         -- etldoc: osm_building_polygon_gen1 -> layer_building:z13
-        SELECT osm_id, geometry, height, levels, min_height, min_level FROM osm_building_polygon_gen1
+        SELECT
+            osm_id, geometry,
+            NULL::int AS render_height, NULL::int AS render_min_height
+        FROM osm_building_polygon_gen1
         WHERE zoom_level = 13 AND geometry && bbox AND area > 1400
         UNION ALL
         -- etldoc: osm_building_polygon -> layer_building:z14_
-        SELECT osm_id, geometry, height, levels, min_height, min_level FROM osm_building_polygon
+        SELECT
+            osm_id, geometry,
+            greatest(5, COALESCE(height, levels*3.66,5))::int AS render_height,
+            greatest(0, COALESCE(min_height, min_level*3.66,0))::int AS render_min_height
+        FROM osm_building_polygon
         WHERE zoom_level >= 14 AND geometry && bbox
     ) AS zoom_levels
     ORDER BY render_height ASC, ST_YMin(geometry) DESC;