[postgis-tickets] [PostGIS] #2602: In some cases ST_Distance (geography) would be faster building the index each time

[PostGIS]

#2602: In some cases ST_Distance (geography) would be faster building the index
each time
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  Reporter:  niqueco  |      Owner:  pramsey
      Type:  defect   |     Status:  new
  Priority:  medium   |  Milestone:  PostGIS Fund Me
 Component:  postgis  |    Version:  trunk
Resolution:           |   Keywords:
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Comment (by pramsey):

 This is true, maybe, but in particular if the traversal of the tree
 happens in some more deterministic order so that the first traversal
 attempts to go down the most likely branches of the tree, causing the
 pruning of branches to be more aggressive. As it stands, it's possible
 that, since the search is depth-first, useless branches can be traversed
 first, resulting in to pruning. Getting a good result from the trees is
 more-or-less a matter of luck: do we happen to traverse effective branches
 of the tree first?

 Sorting the nodes in distance order first would ameliorate this.

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/2602#comment:2>
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