[postgis-users] Optimizer guess makes query 1000x slower?

[rm_postgis at cheapcomplexdevices.com]

On Tue, 15 Jun 2004, strk wrote:
>
> What postgresql version are you using ?
> Postgis built against PostgreSQL <= 74 require you to run
> update_geometry_stats() to build statistics used by the
> selectivity estimator.
> 

I'm using 7.4.2 with postgis-0.8.1 .


Perhaps my problem is that my data is tighly grouped 
in a few cities ranging from Vancouver to Tallahassee.
If the points were evenly distributed over that area, it
probably would have only returned a single row in a
sacramento-sized city.

However with only a dozen or so customers, almost all the
data is in a small number of cities.