[postgis-users] Problem with overlap operator(&&) ?

[Frank Koormann]

* Rob Tester <robtester at gmail.com> [061114 23:26]:
> I recently (with my install of 1.1.5) have run into something that is 
> puzzling me about the overlaps operator. I have two tables that I am 
> comparing the geometry objects using the following SQL:
> 
> select overlaps(a.wkb_geometry,b.wkb_geometry),a.primaryKey,b.primaryKey 
> from az_cr9 a,az_kz b where a.primaryKey=2203 and b.primaryKey=293546 and 
> a.wkb_geometry&&b.wkb_geometry
> 
> This returns one row:
> 
> f;2203;293546
> 
> My question is how does the overlaps operator return TRUE and the overlaps 
> function return FALSE. In fact the two geometries in question do not close 
> to each other. Is this operator broken?

The operator (&&) is working on the bounding boxes while the overlaps()
function is working on the actual geometries.

Best regards,

        Frank

-- 
Frank Koormann                             <frank.koormann at intevation.de>
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