You don't want the GROUP BY. It is grouping the union op on distinct geometry... ie, one per row. Remove it and you'll get what you want, one output row.
P On Tue, May 20, 2008 at 8:49 AM, Bob Pawley <[EMAIL PROTECTED]> wrote: > Hi > > I am attemptijng to use the ST_Union function to collapse three rows from a > table called tank_lin into one row in table called process_dgm. > > Here's what I used - > Insert into graphics.process_dgm(the_geom) > Select ST_Union(the_geom) > from tank_lin > Group by tank_lin.the_geom; > > The result is three rows inserted into process_dgm, each row appearing to be > simple copies of each of the original rows. > I also attempted group by another column but received error 'unknown > geometry'. > > I also tried STR_LineMerge with similar results. > > What am I not considering? > > Bob > _______________________________________________ > postgis-users mailing list > postgis-users@postgis.refractions.net > http://postgis.refractions.net/mailman/listinfo/postgis-users > _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users
