> lisek lichu wrote: >> >> Hello, >> >> I hane in my database 6 linestrings and I want to get the boundary >> rectangle from them (not from each of them) >> >> If i use: >> select AsText(ST_Boundary(the_geom)) from segments; >> >> i get >> >> MULTIPOINT(-8.593025208 41.180818082,-8.594827652 41.187632944) >> MULTIPOINT(-8.594827652 41.187632944,-8.591823578 41.193090782) >> MULTIPOINT(-8.591823578 41.193090782,-8.611950874 41.190119708) >> MULTIPOINT(-8.611950874 41.190119708,-8.613796234 41.179203081) >> MULTIPOINT(-8.613796234 41.179203081,-8.602809906 41.180559684) >> MULTIPOINT(-8.602809906 41.180559684,-8.593025208 41.180818082) >> >> >> but i need one big Boundary. (should I group them by some atribute or >> there is some siplier way to do that?) > > select AsText(ST_Envelope(ST_Collect(the_geom))) from segments; > > Does this work for you? >
What about aggregate function st_extent ? select asText(st_extent(the_geom)) from segments; Nicolas _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
