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Results tagged with union
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user 14466
In set theory, the union (denoted by ∪) of a collection of sets is the set of all distinct elements in the collection. It is one of the fundamental operations through which sets can be combined and related to each other.
4
votes
Merge polygons in postgis
However, if polygon and sliver polygon only have one point in common, then union of these two geometries would not be valid. (or it will be MultiPolygon). …
- 344
7
votes
Accepted
Merge polygons in postgis
SQL:
UPDATE coverage SET the_geom = ST_Union(
(SELECT the_geom FROM coverage WHERE id = :polygon_id),
(SELECT the_geom FROM coverage WHERE id = :sliver_id)
)
WHERE id = :polygon_id;
Is that what Yo …
- 344
4
votes
PostGIS algorithm to unite points of two geometries that are within specified radius
I will try to document things, that I already have tried. Maybe this will help others to provide good ideas.
I read manual about ST_Buffer function:
ST_Buffer
There are interesting options about how …
- 344