[postgis-users] Need help concatentating 60,000 polygon geometries
scott at topozone.com
Thu Oct 4 09:29:45 PDT 2007
I have a table with 60,000 rows.
Each row has a geometry field that is a polygon.
I want to concatenate all of these geometry objects into one big
multipolygon, or at the very least, a polygon, so I can query easily on
one geometry object to see if a point lies within that multipolygon.
I have tried using geomuion, something like below
update layerindex set geom= (select
multi(geomunion(transform(geom,4326))) from stockdrgmeta where
sourcescale > 40000 and sourcescale < 80000) where layername='DRG50'
18 hours into this query I figured it didn't work. A similar query
worked after a while on far less rows.
I then tried using the collect() function, but I couldn't figure out a
way to turn the geometry collection that the function returns into a
Scott Schulthess | Web Developer
Maps a la carte, Inc / TopoZone.com
scott at topozone dot com
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the postgis-users