diff --git a/layers/poi/poi_polygon_update.sql b/layers/poi/poi_polygon_update.sql
index 1e5073d..2840f29 100644
--- a/layers/poi/poi_polygon_update.sql
+++ b/layers/poi/poi_polygon_update.sql
@@ -1,5 +1,11 @@
 -- etldoc:  osm_poi_polygon ->  osm_poi_polygon
-UPDATE osm_poi_polygon  SET geometry=topoint(geometry)
-WHERE ST_GeometryType(geometry) <> 'ST_Point';
 
-ANALYZE osm_poi_polygon;
+CREATE FUNCTION convert_poi_point() RETURNS VOID AS $$
+BEGIN
+  UPDATE osm_poi_polygon SET geometry=topoint(geometry) WHERE ST_GeometryType(geometry) <> 'ST_Point';
+  ANALYZE osm_poi_polygon;
+END;
+$$ LANGUAGE plpgsql;
+
+SELECT convert_poi_point();
+