Perhaps to match a number of people's expectations, there should be an ST_First Point() that is basically ST_StartPoint(ST_GeometryN(ST_Multi(geometry),1)) <div><br></div><div><br><br><div class="gmail_quote">On Tue, Sep 25, 2012 at 4:08 PM, Paul Ramsey <span dir="ltr"><<a href="mailto:pramsey@opengeo.org" target="_blank">pramsey@opengeo.org</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">When ST_NumGeometries == 1, you can run ST_StartPoint on<br>
ST_GeometryN(geom,1). Where ST_NumGeometries > 1 you are in<br>
"interpretation land". What's the start point of a geometry with two<br>
lines?<br>
<span class="HOEnZb"><font color="#888888"><br>
P.<br>
</font></span><div class="HOEnZb"><div class="h5"><br>
On Tue, Sep 25, 2012 at 1:38 PM, David Quinn <<a href="mailto:daithiquinn@gmail.com">daithiquinn@gmail.com</a>> wrote:<br>
> As ST_StartPoint( multilinestring ) returns NULL for PostGIS 2.0<br>
> (<a href="http://postgis.refractions.net/docs/ST_StartPoint.html" target="_blank">http://postgis.refractions.net/docs/ST_StartPoint.html</a> ), what<br>
> approach can be used to identify the start and end points of a<br>
> multilinestring?<br>
><br>
> Thanks,<br>
> David<br>
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