[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
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 Reporter:  realityexists  |       Owner:  pramsey      
     Type:  defect         |      Status:  new          
 Priority:  medium         |   Milestone:  PostGIS 2.0.1
Component:  postgis        |     Version:  2.0.x        
 Keywords:                 |  
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Comment(by pramsey):

 So, yeah, the planner expects one row to pop out of your spatial filter
 and instead 6000 do, which throws off the rest of the plan. Can you strip
 down the query to just the spatial table and filter and see if EXPLAIN
 ANALYZE still gets things that wrong? Because if you can get it down to
 one table and one piece of simple SQL we'll have something to work with,
 repairwise.

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/1828#comment:5>
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