Initial attempt at moving forests with names into their own 'landmarks' layer. (this is heavely copied and pasted from POI)

layers/landmarks/update_lm_polygon.sql

@@ -0,0 +1,78 @@
+DROP TRIGGER IF EXISTS trigger_flag ON osm_lm_polygon;
+DROP TRIGGER IF EXISTS trigger_refresh ON lm_polygon.updates;
+
+-- etldoc:  osm_lm_polygon ->  osm_lm_polygon
+
+CREATE OR REPLACE FUNCTION update_lm_polygon() RETURNS void AS
+$$
+BEGIN
+    UPDATE osm_lm_polygon
+    SET geometry =
+            CASE
+                WHEN ST_NPoints(ST_ConvexHull(geometry)) = ST_NPoints(geometry)
+                    THEN ST_Centroid(geometry)
+                ELSE ST_PointOnSurface(geometry)
+                END
+    WHERE ST_GeometryType(geometry) <> 'ST_Point';
+
+    UPDATE osm_lm_polygon
+    SET subclass = 'subway'
+    WHERE station = 'subway'
+      AND subclass = 'station';
+
+    UPDATE osm_lm_polygon
+    SET subclass = 'halt'
+    WHERE funicular = 'yes'
+      AND subclass = 'station';
+
+    UPDATE osm_lm_polygon
+    SET tags = update_tags(tags, geometry)
+    WHERE COALESCE(tags->'name:latin', tags->'name:nonlatin', tags->'name_int') IS NULL;
+
+    ANALYZE osm_lm_polygon;
+END;
+$$ LANGUAGE plpgsql;
+
+SELECT update_lm_polygon();
+
+-- Handle updates
+
+CREATE SCHEMA IF NOT EXISTS lm_polygon;
+
+CREATE TABLE IF NOT EXISTS lm_polygon.updates
+(
+    id serial PRIMARY KEY,
+    t  text,
+    UNIQUE (t)
+);
+CREATE OR REPLACE FUNCTION lm_polygon.flag() RETURNS trigger AS
+$$
+BEGIN
+    INSERT INTO lm_polygon.updates(t) VALUES ('y') ON CONFLICT(t) DO NOTHING;
+    RETURN NULL;
+END;
+$$ LANGUAGE plpgsql;
+
+CREATE OR REPLACE FUNCTION lm_polygon.refresh() RETURNS trigger AS
+$$
+BEGIN
+    RAISE LOG 'Refresh lm_polygon';
+    PERFORM update_lm_polygon();
+    -- noinspection SqlWithoutWhere
+    DELETE FROM lm_polygon.updates;
+    RETURN NULL;
+END;
+$$ LANGUAGE plpgsql;
+
+CREATE TRIGGER trigger_flag
+    AFTER INSERT OR UPDATE OR DELETE
+    ON osm_lm_polygon
+    FOR EACH STATEMENT
+EXECUTE PROCEDURE lm_polygon.flag();
+
+CREATE CONSTRAINT TRIGGER trigger_refresh
+    AFTER INSERT
+    ON lm_polygon.updates
+    INITIALLY DEFERRED
+    FOR EACH ROW
+EXECUTE PROCEDURE lm_polygon.refresh();