[postgis-devel] [PostGIS] #558: ST_Intersects with Large Number of Points

[PostGIS]

#558: ST_Intersects with Large Number of Points
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 Reporter:  jabts            |       Owner:  pramsey      
     Type:  defect           |      Status:  new          
 Priority:  medium           |   Milestone:  PostGIS 1.5.2
Component:  postgis          |     Version:  1.5.X        
 Keywords:  intersects slow  |  
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 When using a simple square polygon as one of the arguments, and a
 linestring or multilinestring with > 15000 points as the other argument,
 if the query is to return true, it takes a very long time and/or doesn't
 return properly.  Whereas if the query should return false, it returns
 "immediately".

 This problem seems two fold, a) why it would return false quickly and not
 true (seems to me it should be reverse of that) and b) there is a definite
 scaling problem as the number of points go up.

 Attached is a file with some sample linestrings and issues that led to
 this.

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/558>
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