[postgis-users] optimize query

[Pedro Doria Meunier]

Hi List,

 

I'm once again in need of guru advice. J

 

This is the query:

 

select freguesia, distance(geomfromtext('POINT(-9.1533
38.69686)',4326),f.geometry) as thedist 

from freguesias as f 

order by thedist 

limit 1;

 

as you can see it returns the closest polygon to a given point.

 

Problem: 4050 (**detailed**) polygons

exec time: 907 ms

 

The Gist index was created, btw.

 

Is there any way to optimize this query and avoid the dreaded seq scan?

 

Txs in advance!

 

Pedro Doria Meunier.

 

 

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