[postgis-users] How to eliminate small gaps produced by ST_union?

[Bo Victor Thomsen]

Try to use function *st_cleanpolygon* or *st_buffer* with a radius of 0.0.

Regards
Bo Victor Thomsen
Aestas-GIS
Denmark

Den 25-10-2012 18:54, Alexandre Neto skrev:
> I'm trying to Aggregate\Dissolve a set of adjacent, but not touching 
> polygons in Postgis. The geometries were created editing the Postgis 
> table in QGIS created, with snapping and avoid overlap in the layer.
>
> I used ST_Union like this:
>
> SELECT ST_Union(the_geom)
> FROM table;
>
> Small gaps similar to lines appear in the result. This happens when 
> the adjacent polygons do not share the exact same vertices.
>
> Inline image 2
> Is there a way to eliminate this "gaps" or "small angles" within Postgis?
>
> I know that v.clean in GRASS can eliminate small angles, and correct 
> topology, but that would mean I needed to copy the features to GRASS, 
> correct them and copy it back to Postgis.
>
> Thanks in advance,
>
> Alexandre Neto
>
>
>
>
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