Bob, Strange. I don't think I have ever seen quite that error before. What does SELECT ST_GeometryType(the_geom) FROM tank_lin; give you? Regina
________________________________ From: [EMAIL PROTECTED] on behalf of Bob Pawley Sent: Tue 5/20/2008 1:07 PM To: PostGIS Users Discussion Subject: Re: [postgis-users] I'm missing something I tried this - Insert into graphics.process_dgm(the_geom) Select ST_Union(the_geom) from tank_lin; and got the error "Unknown geometry type: 0" Bob ----- Original Message ----- From: "Paul Ramsey" <[EMAIL PROTECTED]> To: "PostGIS Users Discussion" <[email protected]> Sent: Tuesday, May 20, 2008 9:51 AM Subject: Re: [postgis-users] I'm missing something > 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 >> [email protected] >> http://postgis.refractions.net/mailman/listinfo/postgis-users >> > _______________________________________________ > postgis-users mailing list > [email protected] > http://postgis.refractions.net/mailman/listinfo/postgis-users _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users ----------------------------------------- The substance of this message, including any attachments, may be confidential, legally privileged and/or exempt from disclosure pursuant to Massachusetts law. It is intended solely for the addressee. If you received this in error, please contact the sender and delete the material from any computer.
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