Hi everyone,
I've been trying to do a spatial join for a couple of days in different
ways and it never seems to finish. I've done something identical before
in a much larger set of the same data and it worked after a few hours.
I have a polygons (buildings) table with 150,000 records and a points
(land use) table with 170,000 records. I want to calculate how many
points are within each building and add that total to the column 'units'
in the buildings table. The query I run is this:
UPDATE buildings as aa SET units=bb.count FROM (SELECT cc.gid , count(*)
from buildings as cc, landuse as dd
where ST_Within(dd.the_geom, cc.the_geom) group by cc.gid) as bb WHERE
aa.gid=bb.gid;
I also try to create a separate table with the results of the join
before doing the update, but the first step also fails.
Am I doing something wrong? Is there a simple trick that makes this more
efficient?
Thank you,
Jorge
--
Jorge Gil
PhD Candidate
TU Delft / Faculty of Architecture
Department of Urbanism
Chair of Spatial Planning and Strategy
Julianalaan 134
2628 BL Delft
P.O. Box 5043
2600 GA Delft
The Netherlands
www.tudelft.nl
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