[postgis-devel] ST_Expand unexpected behavior

[Mark Cave-Ayland]

David Fuhry wrote:
> Oracle spatial returns a four-ordinate rectangle:
> 
> SQL> select sdo_aggr_mbr(geom) from v_parcel;
> 
> SDO_GEOMETRY(2003, 41100, NULL, SDO_ELEM_INFO_ARRAY(1, 1003, 3), 
> SDO_ORDINATE_ARRAY(2210526.17, 645599.584, 2222040.84, 655437.454))
> 
> Although the returned geometry's sdo_gtype is that of a 2D polygon, the 
> fact that it has only four ordinates means that it should be considered 
> to be a 2D bounding box.  This is mentioned in the docs, but the online 
> 11g doc server is unresponsive, so I can't send a link.
> 
> Thanks,
> 
> Dave

Hmmm I see. So that's almost equivalent to the PostGIS BOX3D type which 
is just for bounding boxes. I'd be interested to the same on other 
spatial databases such as Informix and SQL Server 2008 just to see how 
other people have interpreted the spec.


ATB,

Mark.

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Mark Cave-Ayland
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