[postgis-users] Postgisfunction like Arc's "near"

[Morten Sickel]

Thanks, Steven, the combination of st_dwithin and st_distance seems to do it.

M.


Stephen Woodbridge skrev:
> On 7/27/2013 9:10 AM, Morten Sickel wrote:
>> I would like to repeat an analysis that has been done in arcgis (10.1)
>> in
>> postgis (1.5) (I am running on debian, I could have upgraded, but as my
>> project soon is finished, I would like to, if possible finish it in 1.5)
>>
>> The ananlysis in arc is done using the near table function:
>>
>> http://resources.arcgis.com/en/help/main/10.1/index.html#//00080000001n000000
>>
>> does this exist in postgis 1.5 (or newer)?
>
> This sounds like it just creates a list of features within a a search
> radius of a given feature.
>
> select a.fid as in_fid,
>         b.fid,
>         st_distance(a.the_geom, b.the_geom) as distance
>    from in_feature_table a,
>         features_table b
>   where st_dwithn(a.the_geom, b.the_geom, search_radius)
>   order by a.fid, st_distance(a.the_geom, b.the_geom) asc;
>
> If you want to select the in_feature by its fid then
>
> select a.fid as in_fid,
>         b.fid,
>         st_distance(a.the_geom, b.the_geom) as distance
>    from features_table a,
>         features_table b
>   where a.fid in (list_of_in_feature_ids) and a.fid != b.fid and
>         st_dwithn(a.the_geom, b.the_geom, search_radius)
>   order by a.fid, st_distance(a.the_geom, b.the_geom) asc;
>
> -Steve
> _______________________________________________
> postgis-users mailing list
> postgis-users at lists.osgeo.org
> http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users
>