[postgis-users] Postgis clipping

[strk]

On Wed, Dec 15, 2010 at 05:58:13PM +0100, francescoboccacci at libero.it wrote:
> Hi to all,
> i have a question for you. I have a huge table in postgis where i stored 
> polygon features ( GEOMETRY type). I can load the features in Qgis and for this 
> reason i'd like to search if possible a postigis function that can make clip 
> (or hole) in my a features.
> Pratically I ask to you if there is a possibility to make a clip in a polygon 
> features and how it's works. Please can you send me an example?

 A clip:
  SELECT ST_Intersection(myPoly, myClippingMask);

 A hole:
  SELECT ST_Difference(myPoly, myHolePolygon);

--strk; 

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