[postgis-tickets] [PostGIS] #4672: Cache the return value for getSRSbySRID per transaction

[PostGIS]

#4672: Cache the return value for getSRSbySRID per transaction
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 Reporter:  Raúl Marín   |      Owner:  pramsey
     Type:  enhancement  |     Status:  new
 Priority:  medium       |  Milestone:  PostGIS 3.1.0
Component:  postgis      |    Version:  master
 Keywords:               |
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 Currently the performance of any function that uses getSRSbySRID is
 defined by the time it takes to get the SRS. Since this won't change
 during the execution of the function, we should be able to cache the
 return value and avoid calling it over and over when all the geometries in
 the relation have the same SRID (which I guess is the most common case).

 This affects:
 - ST_AsGML for geometry and geography.
 - ST_AsGeoJSON: geography (always) and geometry (only a crs option is
 set).
 - ST_AsX3D

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/4672>
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