[postgis-tickets] [PostGIS] #2758: ST_Intersects missing rows

[PostGIS]

#2758: ST_Intersects missing rows
---------------------------+------------------------------------------------
 Reporter:  schmiddy       |       Owner:  pramsey
     Type:  defect         |      Status:  new    
 Priority:  medium         |   Milestone:         
Component:  postgis        |     Version:  1.5.X  
 Keywords:  ST_Intersects  |  
---------------------------+------------------------------------------------

Comment(by robe):

 I would expect 0 rows returned for this since the geometry as Paul said is
 so invalid it would fail any intersection matrix test so should always
 return false. Sometimes we do short-circuit that and not do the
 intersection matrix check. If you are using

 {{{

 ST_DWithin(poly, testgeom,0)
 }}}


 you should get the answer you are expecting since that doesn't rely on
 validity.

 What I am a bit concerned about though is I tested your test case on my

 {{{
 POSTGIS="1.5.5" GEOS="3.3.8-CAPI-1.7.8" PROJ="Rel. 4.6.1, 21 August 2008"
 LIBXML="2.7.8" USE_STATS PostgreSQL 9.0.17, compiled by Visual C++ build
 1500, 32-bit
 }}}

 and that returned 0 answers as I would expect.

 But when I did the same test on my


 {{{
 POSTGIS="2.1.2 r12389" GEOS="3.4.2-CAPI-1.8.2 r3924" PROJ="Rel. 4.8.0, 6
 March 2012" GDAL="GDAL 1.10.0, released 2013/04/24" LIBXML="2.7.8"
 LIBJSON="UNKNOWN" RASTER
 }}}

 I get the 3 records your are complaining is not enough.  I also tested on
 my

 {{{
 POSTGIS="2.0.6" GEOS="3.4.2-CAPI-1.8.2 r0" PROJ="Rel. 4.8.0, 6 March 2012"
 GDAL="GDAL 1.10.0, released 2013/04/24" LIBXML="2.7.8" LIBJSON="UNKNOWN"
 (core procs from "2.0.6" need upgrade) RASTER (raster procs from "2.0.6"
 need upgrade) PostgreSQL 9.2.4, compiled by Visual C++ build 1600, 64-bit
 }}}
  and got the same 3 answers.

  I would chuck this as something with our PostGIS 2.0 or 2.1 cache
 implementation or short-circuiting that is not present in 1.5, but you are
 supposedly running a PostGIS older than the 1.5.5 I tested and getting
 more like 2.0 / 2.1 answers.

 Are you absolutely sure you are testing this on 1.5.3.  I think my 1.5.5
 is right and the only install that gives a sane answer to this ill defined
 question :).

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/2758#comment:2>
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