[postgis-devel] [PostGIS] #1828: Estimate returned by geography_gist_selectivity results in slow query plan for ST_DWithin

[PostGIS]

#1828: Estimate returned by geography_gist_selectivity results in slow query plan
for ST_DWithin
---------------------------+------------------------------------------------
 Reporter:  realityexists  |       Owner:  pramsey      
     Type:  defect         |      Status:  new          
 Priority:  medium         |   Milestone:  PostGIS 2.0.1
Component:  postgis        |     Version:  2.0.x        
 Keywords:                 |  
---------------------------+------------------------------------------------

Comment(by realityexists):

 Sure, in that case the query can be as simple as:
 {{{
 SELECT id
 FROM _test_pos
 WHERE ST_DWithin(pos, 'POINT(7 7)', 300000)
 }}}

 The table:
 {{{
 CREATE TABLE _test_pos (
     id serial,
     pos geography(Point,4326)
 );


 WITH data AS
 (
         SELECT generate_series(1, 20000)::float / 1000 AS x
 )
 INSERT INTO _test_pos(pos)
 SELECT ST_MakePoint(x, x)::geography
 FROM data;
 }}}

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/1828#comment:8>
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