[postgis-devel] Minimum number of points in a POLYGON ring?

Mark Cave-Ayland mark.cave-ayland at siriusit.co.uk
Mon Sep 22 08:32:01 PDT 2008


David Fuhry wrote:

> Oracle Spatial itself does no validity checks:
> 
> SQL> create table tt as select sdo_geometry(2003, null, null, 
> sdo_elem_info_array(1,1003,3), sdo_ordinate_array(0,0, 0,1, 1,1, 1,0, 
> 0,0)) as geom from dual;
> 
> Table created.
> 
> SQL> update tt a set a.geom.sdo_ordinates = sdo_ordinate_array(0,1,2);
> 
> 1 row updated.
> 
> SQL> commit;
> 
> Commit complete.
> 
> SQL> select geom from tt;
> 
> SDO_GEOMETRY(2003, NULL, NULL, SDO_ELEM_INFO_ARRAY(1, 1003, 3), 
> SDO_ORDINATE_ARRAY(0, 1, 2))

Thanks David. I have one more question: what happens if you try and 
return the area of your open polygon above?


Many thanks,

Mark.

-- 
Mark Cave-Ayland
Sirius Corporation - The Open Source Experts
http://www.siriusit.co.uk
T: +44 870 608 0063



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