PostGIS: Find nearest roads (represented by linestring) to a given point

nearest-road.sql

/*
 * Road data comes from OpenStreetmap (http://download.geofabrik.de/osm/)
 **/
select st_distance(st_closestpoint(r.the_geog::geometry, wa.location::geometry), wa.location::geometry) as cp
     , r.name
     , r.ref
     , r.ogc_fid
     , r.type
     , st_astext(wa.location)
     , wa.*
from points_of_interest wa, roads r
where wa.id = 'some-poi-id'
  and (r.name is not null or r.ref is not null)
order by cp asc
limit 10
;