[postgis-tickets] [PostGIS] #3418: KNN recheck in 9.5 fails with index returned tuples in wrong order when used in function

[PostGIS]

#3418: KNN recheck in 9.5 fails with index returned tuples in wrong order when
used in function
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  Reporter:  robe     |      Owner:  pramsey
      Type:  defect   |     Status:  new
  Priority:  medium   |  Milestone:  PostGIS 2.4.0
 Component:  postgis  |    Version:  2.2.x
Resolution:           |   Keywords:
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Comment (by robe):

 nwilson5,

 Thanks for the simple example.  I'm surprised this triggered the error,
 but it does for me too.  Last time I saw such simple a test trigger this
 was one I had reported upstream earlier on in KNN development.

 I was hoping I could also make the built in PostgreSQL point datatype
 trigger the problem like I was able to with earlier issue, but
 unfortunately that works fine which suggests it could be a postgis only
 bug:


 {{{

 CREATE TABLE test_pt(geo point);

 INSERT INTO test_pt values ( point(-0.63006, 53.67752) ),
     ( point(-0.1333, 53.35) );


 create index on test_pt using gist (geo);
 select * from test_pt ORDER BY geo::point <->
 '(-0.68333, 53.35)'::point;

 }}}

 Anyrate this example you provided is simpler than the original so
 hopefully easier to debug.

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/3418#comment:9>
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