[postgis-users] POLYGON from LINESTRING

[Bernhard Reiter]

On Thu, Apr 25, 2002 at 07:35:08AM -0700, Paul Ramsey wrote:
> Bernhard Reiter wrote:

> > On Wed, Apr 24, 2002 at 03:46:04PM -0700, Paul Ramsey wrote:
> > > No there is not a simple way. Type casting is not specified in SFSQL.

> My main concern is that if we do somethinglike that now, 
> we open the door to creating incredibly invalid geometries. 

It would be in the responsibility of the developer.
For sure there shouldn't be implicit type casting, this would be
bound to surprises.

> Ends touching is only one of the many criteria for a valid
> polygon, and until we have our topology library we cannot test for all
> the others. Imagine casting a figure 8 into a polygon. Ends touch, but
> it is definately invalid.

Are there provisions against bad INSERT statements for this?
If not, I do not see the chances of creating bad polygons raise.

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