[postgis-users] st_intersection error/bug?

[Düster Horst]

I do have 2 simple linestrings which partly have the same geometry (see
attached dump and image). My aim is to detect the common part of these
two linestrings with the following query:

select st_intersection(a.the_geom, b.the_geom), a.myid
from aline1, aline2

But as the result I get a geometrycollection with one POINT and one
LINESTING. I expected one linestring. Is it a bug??
I'll appreciate any hints.

My system:
Postgis 1.4.0
Geos 3.1.1
Postgres 8.3.6

Best regards
   
Dr. Horst Düster
Stv. Amtschef / GIS-Koordinator 

Kanton Solothurn
Bau- und Justizdepartement
Amt für Geoinformation
SO!GIS Koordination
Rötistrasse 4
CH-4501 Solothurn

Telefon ++41(0)32 627 25 32
Telefax ++41(0)32 627 22 14

mailto:horst.duester at bd.so.ch
http://www.agi.so.ch


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