[postgis-users] Help shaping the future: how do your use of spatial_ref_sys ?

Greg Troxel gdt at lexort.com
Tue Feb 8 17:12:06 PST 2022

Paul Ramsey <pramsey at cleverelephant.ca> writes:

> On Fri, Feb 4, 2022 at 2:23 PM Jim Klassen <klassen.js at gmail.com> wrote:
>> We've been starting at 200000 and using EPSG (misusing the "EPSG"
>> auth kept Proj 4/GDAL/MapServer happier, this likely isn't necessary
>> with Proj 8).  We maintain matching record(s) in our proj4 epsg
>> database file (again this will change as we transition to Proj 8
>> which supports PROJ_AUX_DB).
> Slightly off topic, but a note to your and Paul Moen, that putting
> "EPSG" into the auth_name means that in dereferencing the spatial
> reference info PostGIS ends up calling into proj and saying "is this
> bogus projection EPSG:9999999 projection valid?" which takes time.
> Whereas if auth_name is null, PostGIS just skips right on down to
> using the WKT. And if *that* is null, it can skip directly to using
> the proj4text. So if you're really only using the proj4text, it
> behooves you to leave everything else null.

Separately from the efficiency, I'm also a little conflicted about the
EPSG dataset.  Certainly it's a great contribution, but it doesn't meet
the Free Software definition.  We as a community have more or less made
our peace with that, but it seems best to avoid injecting local
resources into that namespace -- as well as against the spirit of how
EPSG asks the dataset be handled.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 194 bytes
Desc: not available
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20220208/c4ae4768/attachment.sig>

More information about the postgis-users mailing list