use wikidata tag for linking places

Having the same wikidata is a strong indicator that the same place
is meant. There are some assignment errors where the wikidata does
not link to the object itself but to something that mentions the
place. To reduce errors there, prefer same name.

diff --git a/sql/functions/placex_triggers.sql b/sql/functions/placex_triggers.sql
index 0fd0c3bce4aabfd6256dfdb59b1e7c67ad2bdb4d..5c04ad065a9c58211e0bbb3912ac457f4adc76fa 100644 (file)
--- a/sql/functions/placex_triggers.sql
+++ b/sql/functions/placex_triggers.sql
@@ -220,6 +220,21 @@ BEGIN
     END LOOP;
   END IF;
 
+  IF bnd.extratags ? 'wikidata' THEN
+    FOR linked_placex IN
+      SELECT * FROM placex
+      WHERE placex.class = 'place' AND placex.osm_type = 'N'
+        AND placex.extratags ? 'wikidata' -- needed to select right index
+        AND placex.extratags->'wikidata' = bnd.extratags->'wikidata'
+        AND placex.rank_search < 26
+        AND _st_covers(bnd.geometry, placex.geometry)
+      ORDER BY make_standard_name(name->'name') = bnd_name desc
+    LOOP
+      --DEBUG: RAISE WARNING 'Found wikidata-matching place node %', linked_placex.osm_id;
+      RETURN linked_placex;
+    END LOOP;
+  END IF;
+
   -- Name searches can be done for ways as well as relations
   IF bnd_name is not null THEN
     --DEBUG: RAISE WARNING 'Looking for nodes with matching names';

diff --git a/sql/tables.sql b/sql/tables.sql
index 28d664be436b0e993f3d75225e06f981bcdb2a7e..cf51cbe68b058ca6b066d2da226bc42271d9a486 100644 (file)
--- a/sql/tables.sql
+++ b/sql/tables.sql
@@ -177,6 +177,7 @@ CREATE INDEX idx_placex_linked_place_id ON placex USING BTREE (linked_place_id)
 CREATE INDEX idx_placex_rank_search ON placex USING BTREE (rank_search, geometry_sector) {ts:address-index};
 CREATE INDEX idx_placex_geometry ON placex USING GIST (geometry) {ts:search-index};
 CREATE INDEX idx_placex_adminname on placex USING BTREE (make_standard_name(name->'name')) {ts:address-index} WHERE osm_type='N' and rank_search < 26;
+CREATE INDEX idx_placex_wikidata on placex USING BTREE ((extratags -> 'wikidata')) {ts:address-index} WHERE extratags ? 'wikidata' and class = 'place' and osm_type = 'N' and rank_search < 26;
 
 DROP SEQUENCE IF EXISTS seq_place;
 CREATE SEQUENCE seq_place start 1;