[postgis-tickets] [PostGIS] #3864: Sorting by geometry is slower than sorting by geohash

[PostGIS]

#3864: Sorting by geometry is slower than sorting by geohash
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  Reporter:  komzpa   |      Owner:  pramsey
      Type:  defect   |     Status:  new
  Priority:  medium   |  Milestone:  PostGIS 2.4.1
 Component:  postgis  |    Version:  2.3.x
Resolution:           |   Keywords:
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Comment (by pnorman):

 Just to note, `ST_GeoHash(ST_Transform(ST_Envelope(way),4326),10) COLLATE
 "C")` is tweaked based on OSM data, but the selection of 10 was done prior
 to the commit Komzpa linked, the C collation.

 For geohash sorting, the C collation is vital and nearly cuts the time in
 half.

 https://github.com/openstreetmap/osm2pgsql/pull/242 for GeoHash details
 https://github.com/openstreetmap/osm2pgsql/issues/581 for collation
 details.

 The osm_id sort puts a lower bound on the theoretical performance.

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/3864#comment:7>
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