I have a table where there are two geometries: geom_way (for routing roads) and (osm_meta) which is a triangulation from polygons. I use ST_DWithin function (between both geometries) with a distance of 30 meters to divide the costs values for the optimal routing, however, no changes are applied to the resulting cost_greenery column: the ones which should be affected because are in a distance lower than 30m still have the same value as the normal cost. The code below:

UPDATE utrecht_osm_foot_2po_4pgr_duplicate SET cost_greenery =

CASE ST_DWithin(utrecht_osm_foot_2po_4pgr_duplicate.geom_way, utrecht_osm_foot_2po_4pgr_duplicate.osm_meta, 30)

WHEN TRUE THEN utrecht_osm_foot_2po_4pgr_duplicate.cost / 1000

ELSE utrecht_osm_foot_2po_4pgr_duplicate.cost

END;

Do you have any clue on how to solve this?

Thank you for your help!