Changes between Initial Version and Version 1 of UsersWikiExamplesInsidePolygon

Timestamp:

Apr 14, 2009, 9:13:34 AM (15 years ago)

Author:

pierre

Comment:

—

UsersWikiExamplesInsidePolygon

@@ +1 @@
+= Examples Inside Polygon =
+
+
+'''Reinhold Stahlmann [http://postgis.refractions.net/pipermail/postgis-users/2004-January/003867.html asks]:'''
+
+"How can I built an (OGC-conforming) SQL query with PostGIS to select all Points of a given Point-Dataset who have their Geometry within a specific Polygon-Geometry chosen by a label-Field of the Polygon?  For example: All PostGIS-Users.name (Point-Geometry) within 'Sweden' (Polygon-Geometry)"
+
+'''Chris Hodgson [http://postgis.refractions.net/pipermail/postgis-users/2004-January/003868.html answers]:'''
+
+{{{
+SELECT user.name, user.the_geom
+FROM user
+WHERE
+  within( user.the_geom,
+   (SELECT the_geom
+    FROM Country
+    WHERE Country.name = 'Sweden')
+  )
+  AND
+  the_geom &&
+  (SELECT user.the_geom
+   FROM Country
+   WHERE Country.name = 'Sweden')
+
+}}}
+
+
+'''Paul Ramsey tries a different approach:'''
+
+
+{{{
+SELECT user.name, user.the_geom
+FROM user,
+ (SELECT the_geom
+  FROM Country
+  WHERE Country.name = 'Sweden') as country
+WHERE
+  within( user.the_geom, country.the_geom )
+ AND
+  the_geom && country.the_geom
+
+}}}