I guess you can use coalesce to replace the null values with something you want. In your case I think an empty geometry will give you the complete first geometry.
/Nicklas Skickat från min Samsung Mobil. <div>-------- Originalmeddelande --------</div><div>Från: Komяpa <[email protected]> </div><div>Datum:2014-09-02 13:59 (GMT+01:00) </div><div>Till: PostGIS Development Discussion <[email protected]> </div><div>Kopia: PostGIS Users Discussion <[email protected]> </div><div>Rubrik: Re: [postgis-users] [postgis-devel] Is there a reason we don't have an ST_Intersection aggregate function </div><div> </div>There's another thing with ST_Intersection/ST_Difference: sometimes you have to make ST_Difference(geom, (select ST_Union(..,) where ...)) while second operand evaluates to NULL (you shouldn't crop geometry). Currently that leads to ST_Difference pushing out NULL. for my use case, that's not desired semantics - can it be changed? 2014-09-01 4:16 GMT+03:00 Paragon Corporation <[email protected]>: I wasn't sure if we just thought there wasn't much utility in it or if there was a technical obstacle. I would think that would be easier to build than the other aggregates since as you add more geometries it shrinks and the current aggregate state is always the result of the previous state plus new geometry (so no need for an accumulation function or a final state function) and if you ever end up with a geometry collection, you short-circuit out. Thanks, Regina _______________________________________________ postgis-devel mailing list [email protected] http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-devel -- Darafei "Komяpa" Praliaskouski OSM BY Team - http://openstreetmap.by/ xmpp:[email protected] mailto:[email protected]
_______________________________________________ postgis-users mailing list [email protected] http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users
