Hi, The WITH RECURSIVE construct allows to navigate a graph with good performance:
http://blog.cleverelephant.ca/2010/07/network-walking-in-postgis.html http://www.postgresql.org/docs/9.2/static/queries-with.html Nicolas On 21 October 2013 15:19, George Silva <[email protected]> wrote: > I kinda need something similar. My objective was to calculate strahler > stream order and horton's stream order. > > I was feeling that the topology graph next_edge could give me the data that > I need, but I haven't really tried. I also would like to hear if someone > else has the same or something that could be done. > > Any thoughts? > > > On Mon, Oct 21, 2013 at 11:10 AM, Rémi Cura <[email protected]> wrote: >> >> Hey dear list, >> >> Anybody has some advices about navigating trough topology graph (ie given >> a node, find list of next, etc). >> >> I was thinking of using directly the table "edge_data", but it feels like >> a lots of self join. >> >> >> Cheers, >> Rémi-C >> >> _______________________________________________ >> postgis-users mailing list >> [email protected] >> http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users > > > > > -- > George R. C. Silva > SIGMA Consultoria > ---------------------------- > http://www.consultoriasigma.com.br/ > > _______________________________________________ > postgis-users mailing list > [email protected] > http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users _______________________________________________ postgis-users mailing list [email protected] http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users
