[postgis-devel] [PostGIS] #1841: ST_Distance on PostGIS 2.0 is prohibitively slow

[PostGIS]

#1841: ST_Distance on PostGIS 2.0 is prohibitively slow
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 Reporter:  andrewxhill         |       Owner:  pramsey      
     Type:  enhancement         |      Status:  new          
 Priority:  medium              |   Milestone:  PostGIS 2.1.0
Component:  postgis             |     Version:  2.0.x        
 Keywords:  st_distance, speed  |  
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 Running a query to get a pairwise distance calculation for a table takes
 very long. I'm using this to generate a distance matrix for use in R.

 An example query,

 select a.a as g1, b.a as g2, st_distance(a.g, b.g) as d from a join a b on
 a.a<b.a

 Can take minutes on the following data,

 st_distance - no spheroids
 623 polygons with an average of 625 points each (single ring, shell only)

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/1841>
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