[postgis-users] query gist bbox

[Mark Cave-Ayland]

Till Kirchner wrote:

>  Hello together,
> 
> I would like to visualize and query the bboxes used by a gist (rtree) 
> index.
> 
> I thought there should be an easy and fast way to get the maximum extend 
> of geometries stored in a column by simply
> querying the corners of the bbox which covers all data used by the index.
> 
> Is there a function which allows to get information about bboxes used by 
> a gist index?
> 
> Thanks in advance
> 
> Till

Hi Till,

Take a look at the gevel module here: 
http://www.sai.msu.su/~megera/postgres/gist/. I did have a very basic 
prototype which I posted to the -users list a few years ago, but it 
needs some work as the visibility of the bounding boxes (i.e. whether 
they belong to geometry that has been deleted or not) is held in the 
heap and not the index. Unfortunately I don't have the URL to hand at 
the moment.


HTH,

Mark.

-- 
Mark Cave-Ayland - Senior Technical Architect
PostgreSQL - PostGIS
Sirius Corporation plc - control through freedom
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