[postgis-users] st_difference results

[Pedro Costa]

ups forget the ss


Em 28-06-2013 13:20, Pedro Costa escreveu:
> Hi people,
>
> I'm trying to make an st_difference with polygons and lines. But the 
> result is a thousand of features because i get the difference between 
> each polygon on the left side and ALL of the linestrings on the right.
>
> I want only simple linestrings (not multi)  that don't intersect the 
> polygons (ss attached).
> My query:
>
>     CREATE TABLE sample2 AS (
>                         SELECT (st_difference(p.geom,l.geom)
>                         FROM lines l,polygons p
>                         WHERE st_intersects (p.geom, l.geom) = true
>                                 );
>
> Any guess how to limit the result to what i want?
>
> Thanks
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