CTEs always materialise so inline the union zoom level views ⚠️

schema/layers/building.sql

@@ -8,16 +8,15 @@ CREATE OR REPLACE VIEW building_z14 AS (
 
 CREATE OR REPLACE FUNCTION layer_building(bbox geometry, zoom_level int)
 RETURNS TABLE(geom geometry, osm_id bigint, render_height float) AS $$
-    WITH zoom_levels AS (
+    SELECT way, osm_id,
+    least(greatest(3, COALESCE(height, levels*3.66,5)),400)^.7 AS render_height
+    FROM (
         SELECT osm_id, ST_Simplify(way, 10) AS way, height, levels FROM building_z13
         WHERE zoom_level = 13
         UNION ALL
         SELECT * FROM building_z14
         WHERE zoom_level >= 14
-    )
-    SELECT way, osm_id,
-    least(greatest(3, COALESCE(height, levels*3.66,5)),400)^.7 AS render_height
-    FROM zoom_levels
+    ) AS zoom_levels
     WHERE way && bbox
     ORDER BY render_height, ST_YMin(way) DESC;
 $$ LANGUAGE SQL IMMUTABLE;