[postgis-users] RE : Newbie having trouble with Multipolygon file andST_Within

Hugues François hugues.francois at irstea.fr
Tue Jun 25 10:51:57 PDT 2013


This is simply a display problem, not missing geometries.

ST_Within(a.geom, b.geom) returns geometries a which are strictly inside b. This is a big constraint for querying.

You should take a look to st_contains or st_covers to see if one of them match your requirements or make some tests with st_intersects.


-------- Message d'origine--------
De: postgis-users-bounces at lists.osgeo.org de la part de willemb
Date: mar. 25/06/2013 19:44
À: postgis-users at postgis.refractions.net
Objet : [postgis-users] Newbie having trouble with Multipolygon file andST_Within
I have imported a multipolygon shape file into postgis 2.  When I look at the
table I see that only a few of the areas are showing a value in the geometry
column (geom).  When I run a spatial query using something like st_within
against another file it seems to only work on the those rows that have a
geom.  I can't figure out how to populate the missing geometries.  What I
don't understand is that if I use Manifold or QGIS to view the file from
postgis all of the areas are present even though the geometries are not
present for the vast majority of records.  Is there a hidden column? 
Clearly there is something I'm not understanding about Multipolygon files.

View this message in context: http://postgis.17.x6.nabble.com/Newbie-having-trouble-with-Multipolygon-file-and-ST-Within-tp5003597.html
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