[postgis-users] adding additional points to multipoint

[Markus Schaber]

Hi, Christo,

Christo Du Preez wrote:
> The result is:         "MULTIPOINT(1 1,2 2,3 3)"
> The version is:      "POSTGIS="1.1.1" GEOS="2.2.1-CAPI-1.0.1" PROJ="Rel.
> 4.4.9, 29 Oct 2004" USE_STATS"

Okay, this looks fine.

I've got another idea: Is it possible that some of your Multipoints
consist of a single point, and this one is equal to the point you add?
This could result in your query generating POINTs instead.

# select asText(geomunion('MULTIPOINT(1 1)','POINT(1 1)'));
   astext
------------
 POINT(1 1)
(1 row)

You can fix it by wrapping the geomunion in a multi() function:
# select asText(multi(geomunion('MULTIPOINT(1 1)','POINT(1 1)')));
     astext
-----------------
 MULTIPOINT(1 1)
(1 row)





If this does not fix it, I don't have any more ideas...


Markus

-- 
Markus Schaber | Logical Tracking&Tracing International AG
Dipl. Inf.     | Software Development GIS

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