Ciprian Talaba wrote: > Thank you about this info. I will probably start with the last approach > (using planet_osm_rels and planet_osm_line tables) because this will > keep my code separate from osm2pgsql. I will try to publish my tries > because I believe others will be interested in something like this.
Some code snippets that may be useful in your endeavours: Unnest an array. Later postgresql has this builtin, I think: CREATE OR REPLACE FUNCTION unnest(ANYARRAY) RETURNS SETOF ANYELEMENT LANGUAGE SQL AS $$SELECT $1[i] FROM generate_series(array_lower($1,1),array_upper($1,1)) i;$$; Unnesting a relation from planet_osm_rels gives you a list of all members, with the first character telling you what type of object it is, with the rest being the osm id. Unnest only way members of a relation in the planet_osm_rels table: CREATE OR REPLACE FUNCTION unnest_rel_members_ways(ANYARRAY) RETURNS SETOF ANYELEMENT LANGUAGE SQL AS $$SELECT substring($1[i] from E'w(\\d+)') FROM generate_series(array_lower($1,1),array_upper($1,1)) i WHERE $1[i] LIKE 'w%';$$; select unnest_rel_members_ways(members) as members from planet_osm_rels where id=<your relation id>; This gives you a list of only way ids, 1 per row, with the first 'w' character stripped. You still need some way to join the member role in the results. I didn't get that far when I wrote the unnest function, as I didn't need the role at the time. -- Lennard _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk
