Nominatim/lib-sql/functions/postcode_triggers.sql
Sarah Hoffmann 784dad866f change distance computation between place and address part
Instead of computing the distance to the centroid of the area
compute the distance of the area to the centroid of the feature.
This means we give preference to the area that covers the centroid.
It's still a heuristics but one that is a bit less random.
2022-04-22 14:32:09 +02:00

48 lines
1.2 KiB
PL/PgSQL

-- SPDX-License-Identifier: GPL-2.0-only
--
-- This file is part of Nominatim. (https://nominatim.org)
--
-- Copyright (C) 2022 by the Nominatim developer community.
-- For a full list of authors see the git log.
-- Trigger functions for location_postcode table.
-- Trigger for updates of location_postcode
--
-- Computes the parent object the postcode most likely refers to.
-- This will be the place that determines the address displayed when
-- searching for this postcode.
CREATE OR REPLACE FUNCTION postcode_update()
RETURNS TRIGGER
AS $$
DECLARE
partition SMALLINT;
location RECORD;
BEGIN
IF NEW.indexed_status != 0 OR OLD.indexed_status = 0 THEN
RETURN NEW;
END IF;
NEW.indexed_date = now();
partition := get_partition(NEW.country_code);
SELECT * FROM get_postcode_rank(NEW.country_code, NEW.postcode)
INTO NEW.rank_search, NEW.rank_address;
NEW.parent_place_id = 0;
FOR location IN
SELECT place_id
FROM getNearFeatures(partition, NEW.geometry, NEW.geometry, NEW.rank_search)
WHERE NOT isguess ORDER BY rank_address DESC, distance asc LIMIT 1
LOOP
NEW.parent_place_id = location.place_id;
END LOOP;
RETURN NEW;
END;
$$
LANGUAGE plpgsql;