Read point data for closest road in PostGIS:
SELECT cp.*, r.the_geom FROM roads r, (SELECT p.* ,r.id from point p, roads ro ORDER BY ST_Distance(p.the_geom, ro.the_geom) ASC LIMIT 1) as cp WHERE cp.id = r.id
cp alias should have one closest road for every point, WHERE ST_Dwithin(geom,geom) < 1 should make search faster
Little closer answer is (in PostGIS)
SELECT r.*, p.* FROM roads r, points p WHERE ST_Intersects(r.geom,p.geom) IS TRUE
That returns roads rows several times if there are more than one intersection on road
SELECT r.the_geom, r.gid , p.name INTO roads_with_names WHERE ST_Intersects(r.geom,p.geom) IS TRUE GROUP BY r.gid, p.name
Return only one row per road (i'm not 100% how crosstab works)
select * from crosstab('select r.the_geom, 'name' , r.name from roads_with_names r ORDER 1,2) AS ct(the_geom geometry, name text, name2 text , name3 text , name 4 text );
Or use LEFT join on road id. There is several ways to do it
Should create new table which has road geoms, gid and name from point table. There should not be any dublicate r.gid + p.name rows. In QGIS you can define label field from database (assuming that you have PostGIS source) from Layers properties.
You may need to use first answer if your data does not intersect.
Closest point on road in PostGIS is
SELECT ST_ClosestPoint(r.geom, po.geom) as closest_point, r.id FROM roads r, (SELECT p.* ,r.id from point p, roads ro ORDER BY ST_Distance(p.the_geom, ro.the_geom) ASC LIMIT 1) as po where r.id = po.id
Above should return point geometry on road which is closest to point on point table which is closest to road.