[postgis-users] Method to remove overlaps in a layer

[Sandro Santilli]

On Wed, Apr 11, 2012 at 02:53:07PM -0400, Pierre Racine wrote:
> An even simpler example leads to another type of error:
> 
> SELECT CreateTopology('topo3',0, 10);
> 
> DROP TABLE IF EXISTS ovlp.test03;
> CREATE TABLE ovlp.test03 AS
> SELECT 1 id, ST_GeomFromText('POLYGON((0 1, 2 2, 2 0, 0 1))') geom
> UNION ALL
> SELECT 2 id, ST_GeomFromText('POLYGON((1 1, 3 2, 3 0, 1 1))') geom
> 
> CREATE TABLE ovlp.test03_topo (id integer);
> 
> SELECT AddTopoGeometryColumn('topo3', 'ovlp', 'test03_topo', 'topo', 'POLYGON'); -- 1
> 
> INSERT INTO ovlp.test03_topo (id, topo)
> SELECT id, topology.toTopoGeom(geom, 'topo3', 1)
> FROM ovlp.test03
> 
> gives:
> 
> ********** Error **********
> 
> ERROR: SQL/MM Spatial exception - edge crosses node.

Ouch, you're lucky. It kills the backend here !!
I'm on it.

--strk; 

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