[postgis-devel] PostGIS 3 thought experiment

[Paul Ramsey]

What else is on everyone's wish list? Preferably things you'd do if
you didn't think everyone would shoot you down for being too
disruptive.

https://trac.osgeo.org/postgis/wiki/PostGIS3

* Break out a postgis_raster extension with a postgis dependency, so
raster support becomes optional.
* Require installation in a 'postgis' schema, always and for ever

* Yet another serialization, this time changing to use external
storage type, and adding our own compression scheme for coordinates.
  * An uncompressed header, so header info can always be efficiently
"sliced" and read, even for very large objects
  * A hash key for use in fast and small equality comparisons (for use
in cached comparison code)
  * A compression format optimized for doubles
  * Other compression formats with other tradeoffs (?) like TWKB for
higher ratio with precision loss
  * Implies indirection in coordinate access again: smaller, more
efficient must be balanced against direct access to coordinates

* Move up to "modern" C and use whatever cool features we like from that
* Modern GEOS version requirement?
* Some major GEOS surgery to allow memory management by palloc?
* Some major GEOS surgery to build coordinateSequence directly on top
of PostGIS pointlists?