[PostGIS] #5750: Overestimated extent from ST_EstimatedExtent result for geography column

[PostGIS]

#5750: Overestimated extent from ST_EstimatedExtent result for geography column
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  Reporter:  strk     |      Owner:  pramsey
      Type:  defect   |     Status:  new
  Priority:  medium   |  Milestone:  PostGIS Fund Me
 Component:  postgis  |    Version:  master
Resolution:           |   Keywords:  extent, geography
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Changes (by pramsey):

 * milestone:  PostGIS 3.5.0 => PostGIS Fund Me

Comment:

 Copying in note from chat

 this is expected… so the statistics and the index both probably have an
 idea of the extent that matches what’s in your head (something taller than
 it is wide). But our path to converting that geocentric box into something
 planar is this:

 * find all the corners of the geocentric box
 * find the average corner (which will be fairly central) so call it the
 center
 * find the furthest corner from the center, make the distance to that
 corner by the radius
 * you now have a “cap”, a center and a radius, that contains the original
 box, however said “cap” is as wide as it is tall
 * find the planar bounds of  that cap, which also ends up as wide as it is
 tall
 (edited)

 So the problem is, again, converting from a geocentric bounding volume to
 a planar rectangle that works in all cases. Your example extent does in
 fact contain the input, just with a lot of over coverage, but still:
 contract met!
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Ticket URL: <https://trac.osgeo.org/postgis/ticket/5750#comment:2>
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