[postgis-devel] [PostGIS] #1842: WHERE ST_Intersects causes VM to balloon

[PostGIS]

#1842: WHERE ST_Intersects causes VM to balloon
-----------------------+----------------------------------------------------
 Reporter:  darkblueb  |       Owner:  pramsey     
     Type:  defect     |      Status:  new         
 Priority:  medium     |   Milestone:  PostGIS GEOS
Component:  postgis    |     Version:  1.5.X       
 Keywords:             |  
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 a particular query causes allocations of VM that eventually cause the
 process to be killed, before completion. The same query on the same data
 on another host does not show this behavior. Test query, sample data and
 machine descriptions are enclosed.

 One workaround is to use
 {{{
  ... WHERE  a.wkb_geometry && b.wkb_geometry;
 }}}
   instead, but that causes NULL and POINT results along with the desired
 intersection results to be generated.   Another workaround may be to
 setting RLIMIT_VMEM for Postgres under Linux/POSIX ?

 {{{
 CREATE TABLE lt_grid_intersect_marin_intersmethod
  as
 SELECT
    ST_Intersection(g.wkb_geometry, l.wkb_geometry) as wkb_geometry,
         id_grid,
         landtype,
         fmmp_class
 FROM grid150m_marin_subset as g, lt_marin_subset as l
 WHERE ST_Intersects(g.wkb_geometry, l.wkb_geometry);
 }}}

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/1842>
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