On Mon, Oct 15, 2012 at 11:37:08AM +0000, Astrid Bjørnerød wrote: > No, I have really not understood the way to get a link between the > relation-table and the originally geo-table.
A TopoGeometry object represents that link. > I have a table geoTable. > All I want is to make query which returns the values of left and right > polygons, like this : > Update geoTable set newValue = leftFace.value where geoTable.field1 is > null; --if leftFace.Area > rightFace.Area or > Update geoTable set newValue = rightFace.value where geoTable.field1 is > null; --if leftFace.Area < rightFace.Area > > What is the mapping between myTopo.relation element_id and the geoTable and > how do I get this (which topology functions)? You only want to query the relation table to know the composition of your TopoGeometry. In your case this would probably be a list of face identifiers. But you can also use functions to get that information: GetTopoGeomElementArray or GetTopoGeomElements. You ask: "[..] I want [..] the values of left and right polygons" Left and right of what ? In the topology model we refer to "left" and "right" of an edge. Is that what you're looking for ? --strk; http://www.cartodb.com - Map, analyze and build applications with your data ~~ http://strk.keybit.net _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users
