[postgis-users] point to multipoint

[Mehmet Sirin]

.. don't ask why im not just using min(st_distance) to solve that nearest
thing problem :)

you should know that all the unioned points are having the same coordinates.

2009/11/26 Mehmet Sirin <m.sirin07 at googlemail.com>

> hi, is someone out there who can explain how to make several points to a
> multipoint.. i tried st_union and st_collect but what comes out is a
> multilinestring and geometrycollection(multilinestring(..)) respectively.
>
> code with which the unwilling multilinestring happens:
>
> select astext(st_union(c.geom_4326)) from (
>     select * from (select * from(
>         select *,buffer(geom_4326,0.01)as buff from gc_berechnet where
> name='Neuer Graben' and
>         gemeinde='Osnabrück')a)b, zip_coordinates zc
> where contains(buff,zc.geom) )c
>
>
> what i want to do:
> 1.buffering a pointt (A) with a radius of 1km
> 2.take a look which other points lie in this buffer polygon
> 3.find out which point inside the buffer is nearest to the first point (A)
> i buffered.
> important for 3. : when having a multipoint i can easily use st_distance to
> determine the closest point to point (A)
>
>
> you can tell me how to create multipoint ? then i love you^^
>
>
>
> leaving you kind regards
> mehmet sirin c.
>
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