I have a problem with intersection function. I built my query following http://manual.linfiniti.com/en/postgis/geometry.html, 5.7 section.
I made my clip object, a red linestring frame:
But after the clip(intersect) operation, something is wrong:
create table roads_clip as select st_intersection(a.geom, b.geom), b.* from clip as a, roads as b where not st_isempty(st_intersection(st_setsrid(a.geom,23700), b.geom));
Roads layer contains multiline object and intersection cut roads where intersects the red frame.
I would like a result similar to this: