[postgis-users] st_union and linestringM

[Lauri Kajan]

Hi all,

I'm trying to make a union of geometries with M-values.
But ST_Union seems to drop all the M-values.

Or am I doing something wrong?
Here is a sample query:
  select st_asewkt(st_union('LINESTRINGM(0 0 0, 1 1
1)'::geometry,'LINESTRINGM(1 1 1, 2 2 2)'::geometry));
Output of this is
"MULTILINESTRING((0 0,1 1),(1 1,2 2))"

Same happens with 4D LINESTRING geometries. Output is only XYZ.

Is there a other way to accomplish what I want or is this a bug?


Thanks

-Lauri