Question

I’m developing an application using osm data and I have some questions:

1. I have a postgresql database with osm data imported with osm2po tool. My goal is to be able to route between different POIs. There are POI that aren’t source/target in “at_2po_4pgr” table. Would be a feasible solution to perform a function call “find_nearest_node_within_distance” (e.g. SELECT * FROM find_nearest_node_within_distance(‘POINT(-3.6785434 42.6798754)’, 0.1, ‘at_2po_4pgr’))? How I could adjust that offset to the route?

2. I have no clear what columname “cost” represents. Is it related to the distance, time or is only a symbolic value?

3. Finally, Is there any tool or node/way tag in openstreetmap to obtain a POI rate as with the Google Places service ?(here nodes/places have a label/tag with the rating. e.g. <rating>3.2</rating>)

Thanks in advance and excuse my poor english.

Answer 1

1. Check THIS thread, At the answers you will find the solution (find_nearest_node_within_distance function from pgrouting scripts)

2. cost means cost. It depends you, how do you set that. It is the length of the given way by default, but you could set its value to distance/max_speed (results time).
   Another possibility is to set the costs of a given type of way very high (>1000) resulted the route planner will ignore that type of way (ex.: tracks, footways, motorways).