[postgis-devel] spatial_ref_sys maintainance

[Even Rouault]

Le jeudi 28 janvier 2016 10:20:02, Sandro Santilli a écrit :
> I've seen spatial_ref_sys was first updated with some automatic
> export from GDAL and then manually tweaked to add "historical manual
> diffs" [1].
> 
> Is the process documented somewhere ? How can we ensure these manual
> diffs are always retained in the future ?
> 
> Also, updating that table currently requires manually tweaking
> the extensions/postgis/sql_bits/mark_editable_objects.sql.in file,
> which is error prone [2]. Can it be automated to reduce the risk ?

It seems odd that those tweakings are restricted to PostGIS only. They should 
also apply to GDAL, libgeotiff, proj.4 (and depending QGIS etc.) as well to 
avoid inconsistencies.

Given the current chain of generation, they could be dealt as overrides in 
libgeotiff .csv files, which would cause all downstream (GDAL, proj.4 & PostGIS) 
to inherit from them. 

From what I can see, the overrides are mainly for SRS with Datum = 
New_Zealand_Geodetic_Datum_1949 (addition of +nadgrids=nzgd2kgrid0005.gsb, 
actually this one could also be dealt in proj.4 itself in the definition of the 
nzgd49 datum ), EPSG:2065 (S-JTSK (Ferro) / Krovak), EPSG 3844 (Pulkovo 
1942(58) / Stereo70), and the addition of EPSG:900913. 
Some justification of the overrides of EPSG:2066 and EPSG 3844 would be useful.

Even

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