[postgis-devel] I want boxes

[Sandro Santilli]

On Tue, Nov 08, 2011 at 10:20:32AM -0800, Chris Hodgson wrote:
> I'm guessing that if A and B are large geometries and/or already
> have BBox caches, this:
> 
> ST_Envelope(ST_Collect(ST_Envelope(A), ST_Envelope(B)));
> 
> would be faster... should save copying all the coordinates.

Yes, you're right.

> If I'm right, perhaps a non-agreggate st_extent() function is in order, because that doesn't seem like such a weird thing to do yet requires a lot of function calls to do efficiently.

Note that ST_Extent drops dimensionality and SRID.

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