[postgis-users] navigation trough topology graph

[Nicolas Ribot]

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 <georger.silva at gmail.com> 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 <remi.cura at gmail.com> 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
>>
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>
>
>
>
> --
> George R. C. Silva
> SIGMA Consultoria
> ----------------------------
> http://www.consultoriasigma.com.br/
>
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