Hi I'm trying to make a (new, larger) multipolygon from a number of rows that are selected using an aggregate function ST_Collect. The problem is that the ST_Collect creates a geometrycollection which I can't work out how to merge into a new multipolygon, even though the source column only contained multipolygon. I've RTFM a few times... ...help?!
My current insert statement looks something like this - I get no error, but the output is null in the output column. insert into my_output_table (id, the_geom, debug_text) select s.id, ST_MPolyFromText(ST_AsText(ST_Collect(s.the_geom))), ST_AsText(ST_Collect(s.the_geom)) from my_source_table s group by id; The debug_text column gets filled with lots of nice WKT of GEOMETRYCOLLECTION, but we kind of expected that already ;-) Any clues greatly appreciated. Otherwise I will be forced to do something horrible in Perl like do the select, dismember each MULTIPOLYGON record in the source table grouped as per the select above and then craft WKT to make an insert statement to populate my output table. /Surely/ I don't have to resort to this kludgery? Regards Marcus _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
