diff --git a/layers/housenumber/housenumber_centroid.sql b/layers/housenumber/housenumber_centroid.sql
index 101f701f..1d1cf83a 100644
--- a/layers/housenumber/housenumber_centroid.sql
+++ b/layers/housenumber/housenumber_centroid.sql
@@ -7,3 +7,37 @@ END;
 $$ LANGUAGE plpgsql;
 
 SELECT convert_housenumber_point();
+
+-- Handle updates
+
+CREATE SCHEMA housenumber;
+
+CREATE TABLE IF NOT EXISTS housenumber.updates(id serial primary key, t text, unique (t));
+CREATE OR REPLACE FUNCTION housenumber.flag() RETURNS trigger AS $$
+BEGIN
+    INSERT INTO housenumber.updates(t) VALUES ('y')  ON CONFLICT(t) DO NOTHING;
+    RETURN null;
+END;    
+$$ language plpgsql;
+
+CREATE OR REPLACE FUNCTION housenumber.refresh() RETURNS trigger AS
+  $BODY$
+  BEGIN
+    RAISE LOG 'Refresh housenumber';
+    SELECT convert_housenumber_point();
+    DELETE FROM housenumber.updates;
+    RETURN null;
+  END;
+  $BODY$
+language plpgsql;
+
+CREATE TRIGGER trigger_flag
+    AFTER INSERT OR UPDATE OR DELETE ON osm_housenumber_point
+    FOR EACH STATEMENT
+    EXECUTE PROCEDURE housenumber.flag();
+
+CREATE CONSTRAINT TRIGGER trigger_refresh
+    AFTER INSERT ON housenumber.updates
+    INITIALLY DEFERRED
+    FOR EACH ROW
+    EXECUTE PROCEDURE housenumber.refresh();
diff --git a/layers/poi/poi_polygon_update.sql b/layers/poi/poi_polygon_update.sql
index 2840f297..51259e5c 100644
--- a/layers/poi/poi_polygon_update.sql
+++ b/layers/poi/poi_polygon_update.sql
@@ -9,3 +9,36 @@ $$ LANGUAGE plpgsql;
 
 SELECT convert_poi_point();
 
+-- Handle updates
+
+CREATE SCHEMA poi;
+
+CREATE TABLE IF NOT EXISTS poi.updates(id serial primary key, t text, unique (t));
+CREATE OR REPLACE FUNCTION poi.flag() RETURNS trigger AS $$
+BEGIN
+    INSERT INTO poi.updates(t) VALUES ('y')  ON CONFLICT(t) DO NOTHING;
+    RETURN null;
+END;    
+$$ language plpgsql;
+
+CREATE OR REPLACE FUNCTION poi.refresh() RETURNS trigger AS
+  $BODY$
+  BEGIN
+    RAISE LOG 'Refresh poi';
+    SELECT convert_poi_point();
+    DELETE FROM poi.updates;
+    RETURN null;
+  END;
+  $BODY$
+language plpgsql;
+
+CREATE TRIGGER trigger_flag
+    AFTER INSERT OR UPDATE OR DELETE ON osm_poi_polygon
+    FOR EACH STATEMENT
+    EXECUTE PROCEDURE poi.flag();
+
+CREATE CONSTRAINT TRIGGER trigger_refresh
+    AFTER INSERT ON poi.updates
+    INITIALLY DEFERRED
+    FOR EACH ROW
+    EXECUTE PROCEDURE poi.refresh();