[postgis-users] ST_Intersects

[danny]

Hello,

I'm wondering if it's normal to have a 420 second response time for the
following query.
A spatial index has been set on the spatial field (the_geom) and other
important fields (like sitecode). I've generously tweaked the memory options
for postgresql.
With such a response time I would have to let my query run for half a year
before getting the answer I'm interested in! :)

Anybody know how I can boost up the process or is it doomed to always be so
slow? The europe_layer is indeed a complex polygon....

select  st_intersects(a.the_geom,b.the_geom) from sites a,  europe_waters b
where a.sitecode = 'xxxx';

"Nested Loop  (cost=0.00..496.18 rows=1310 width=35786)"
"  ->  Seq Scan on sites a  (cost=0.00..453.43 rows=1 width=35754)"
"        Filter: ((sitecode)::text = 'xxxx'::text)"
"  ->  Seq Scan on europe_waters b  (cost=0.00..23.10 rows=1310 width=32)"

My true objective would be to join thses two tables through an st_intersects
but for the time it is unconceivable.

Many thanks,

Erik
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