Thanks Steve, that looks like what I need. Best regards, Rich
On Tue, Jan 3, 2012 at 7:49 AM, Stephen Woodbridge <wood...@swoodbridge.com> wrote: > On 1/3/2012 9:19 AM, Richard Greenwood wrote: >> >> This seems so simple that I'm embarrassed to ask, but, putting my >> pride in my pocket... >> >> I want to aggregate two linestrings into one. The endpoint of the >> first linestring is coincident with the start point of the second. >> Using st_collect() or st_union() I get a multiLineString with 2 >> geometries. How can I get a single linestring, or a multiLineString >> with just 1 geometry? >> >> I cases where I aggregate linestrings that do not have coincident >> start/end points I do want multiLineStrings with multiple geometries. >> >> I tried the st_dump() "trick" with no better luck: >> >> SELECT label, st_numgeometries(ST_Collect (f.the_geom )) >> FROM ( SELECT label, (ST_Dump (wkb_geometry )).geom As the_geom >> from road_cl >> ) As f >> GROUP BY label >> >> Basically I'm looking for the opposite of st_multi() >> >> Thanks, >> Rich >> > > Hi Rich, > > I think you are looking for: > > http://postgis.refractions.net/docs/ST_LineMerge.html > > -Steve > > _______________________________________________ > postgis-users mailing list > postgis-users@postgis.refractions.net > http://postgis.refractions.net/mailman/listinfo/postgis-users -- Richard Greenwood richard.greenw...@gmail.com www.greenwoodmap.com _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users
