[postgis-users] ST_Extent of table

[Paul Ramsey]

Javier,
You can get a fast, imprecise extent from st_estimated_extent. We
should update/change it to use the index top page, but for now it uses
the index stats, which means it is sometimes slightly underdetermined,
so you might need to grow it by 10-25% depending on your use case.
Paul

On Mon, Sep 19, 2011 at 9:29 AM, Javier de la Torre
<jatorre at vizzuality.com> wrote:
> Hi all,
> I need to calculate the extent of a full table. My understanding is that
> this function will do a full scan of the table to calculate it. Is it
> possible to get the extent of the table from the index somehow so that is
> not needed to scan the full table? I also dont need it very precise if that
> helps in any way.
> Thanks!
>
> Javier de la Torre
> @jatorre
> Vizzuality
> 148 Lafayette St. PH, New York, 10013,USA
> Hortaleza 48 1, 28004,Madrid,Spain
> +1 347 320 7715
> +34 689 41 4420
> www.vizzuality.com
> @vizzuality
>
>
>
>
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