[postgis-users] TopologyException: no outgoing dirEdge found

[Frank Koormann]

Moin,

[Repost to postgis-users for the records]

* Andreas Laggner <bloediandi at web.de> [070809 09:03]:
> i had the same idea and the downloads for the geos3 were already done - 
> with the suggestion from Frank (thanks a lot to you) i installed the new 
> version immediately. The region of LK Gifhorn were intersected WITHOUT 
> errors than!! Now i have to improve the performance: Gifhorn takes 19 
> seconds in ArcGis and 6 Minutes with PostGis. The intersection InVeKos 
> with Atkis all over lower saxony (niedersachsen) runs since 14 hours 
> now!!! That??s overkill. Does someone know how to make PostGis faster in 
> GIS functions?

>From your earlier post I cannot see that you are using indexes on the
geometry columns:
- You should have indexes on your geometry columns in teh source table.
- You explicitely have to use them by including a bounding box operation
  into your queries, e.g.

  insert into intersect_gf2 
        select t1.gid,intersection(t1.the_geom, t2.the_geom) 
        from gf_buk t1, gf_veg2 t2
        where t1.the_geom && t2.the_geom;

  This reduces the set of geometries to be processed by the (expensive)
  intersection, geomunion, ... to a reasonable amount.

Regards,

        Frank
 
-- 
Frank Koormann  |  ++49-541-335 08 30  |  http://www.intevation.de/
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