Compute separate concurrency_index on osm_route_member (#1135)

Closes #1134 

Adds a `concurrency_index` column to `osm_route_member` as described in #1134.  For example, listing concurrencies on a [segment of the Washington Bridge](https://www.openstreetmap.org/way/43080535) in Providence, Rhode Island, USA:

```
openmaptiles=# select osm_id, network, ref, network_type, name, concurrency_index from osm_route_member where member=43080535 order by concurrency_index asc;
  osm_id  | network | ref | network_type  |     name      | concurrency_index
----------+---------+-----+---------------+---------------+-------------------
 -1694950 | US:I    | 195 | us-interstate | I 195 (RI/MA) |                 1
 -2308410 | US:US   | 6   | us-highway    | US 6 (RI)     |                 2
 -1347856 | US:US   | 1A  | us-highway    | US 1A (RI)    |                 3
 -2309143 | US:US   | 44  | us-highway    | US 44 (RI)    |                 4
(4 rows)
```

layers/transportation_name/update_route_member.sql

@@ -91,3 +91,12 @@ CREATE INDEX IF NOT EXISTS osm_route_member_name_idx ON osm_route_member ("name"
 CREATE INDEX IF NOT EXISTS osm_route_member_ref_idx ON osm_route_member ("ref");
 
 CREATE INDEX IF NOT EXISTS osm_route_member_network_type_idx ON osm_route_member ("network_type");
+
+ALTER TABLE osm_route_member ADD COLUMN IF NOT EXISTS concurrency_index int;
+
+INSERT INTO osm_route_member (id, concurrency_index)
+  SELECT
+    id,
+    ROW_NUMBER() over (PARTITION BY member ORDER BY network_type, network, LENGTH(ref), ref) AS concurrency_index
+  FROM osm_route_member
+  ON CONFLICT (id) DO UPDATE SET concurrency_index = EXCLUDED.concurrency_index;

layers/transportation_name/update_transportation_name.sql

@@ -42,16 +42,12 @@ FROM (
         CASE WHEN highway IN ('footway', 'steps') THEN layer END AS layer,
         CASE WHEN highway IN ('footway', 'steps') THEN level END AS level,
         CASE WHEN highway IN ('footway', 'steps') THEN indoor END AS indoor,
-        ROW_NUMBER() OVER (PARTITION BY hl.osm_id
-            ORDER BY rm.network_type) AS "rank",
         hl.z_order
     FROM osm_highway_linestring hl
-            LEFT JOIN osm_route_member rm ON
+            LEFT OUTER JOIN osm_route_member rm ON rm.member = hl.osm_id AND rm.concurrency_index=1
-        rm.member = hl.osm_id
     WHERE (hl.name <> '' OR hl.ref <> '')
       AND NULLIF(hl.highway, '') IS NOT NULL
-) AS t
+) AS t;
-WHERE ("rank" = 1 OR "rank" IS NULL);
 CREATE INDEX IF NOT EXISTS osm_transportation_name_network_osm_id_idx ON osm_transportation_name_network (osm_id);
 CREATE INDEX IF NOT EXISTS osm_transportation_name_network_name_ref_idx ON osm_transportation_name_network (coalesce(name, ''), coalesce(ref, ''));
 CREATE INDEX IF NOT EXISTS osm_transportation_name_network_geometry_idx ON osm_transportation_name_network USING gist (geometry);
@@ -308,18 +304,14 @@ BEGIN
             CASE WHEN highway IN ('footway', 'steps') THEN layer END AS layer,
             CASE WHEN highway IN ('footway', 'steps') THEN level END AS level,
             CASE WHEN highway IN ('footway', 'steps') THEN indoor END AS indoor,
-            ROW_NUMBER() OVER (PARTITION BY hl.osm_id
-                ORDER BY rm.network_type) AS "rank",
             hl.z_order
         FROM osm_highway_linestring hl
                 JOIN transportation_name.network_changes AS c ON
             hl.osm_id = c.osm_id
-                LEFT JOIN osm_route_member rm ON
+                LEFT OUTER JOIN osm_route_member rm ON rm.member = hl.osm_id AND rm.concurrency_index=1
-            rm.member = hl.osm_id
         WHERE (hl.name <> '' OR hl.ref <> '')
           AND NULLIF(hl.highway, '') IS NOT NULL
-    ) AS t
+    ) AS t;
-    WHERE ("rank" = 1 OR "rank" IS NULL);
 
     -- noinspection SqlWithoutWhere
     DELETE FROM transportation_name.network_changes;