[postgis-devel] Valid SRIDs

[Kevin Neufeld]

Not to long ago in the bug tracker, a user suggested that 
ST_AddGeometryColumns() should error out if the supplied SRID is not in 
spatial_ref_sys. 

What does the team here think?  Should PostGIS be responsible for 
ensuring correct parameters?  (We currently raise exceptions for all 
other invalid parameters). If so, the solutions I see are:
1. Modify the plpgsql function to error if the SRID does not exist
2. Put a foreign key constrain on geometry_columns referencing 
spatial_ref_sys.

Essentially, if we do this, loading spatial_ref_sys into PostGIS will no 
longer be an optional part of the install process.  This also means that 
we'll have to add a dummy record for an SRID of -1 and perhaps 0.

Personally, I'm undecided.  I like enforcing data integrity - it has 
saved me many times in the past ... not to mention it's good practice.  
But putting the onus on the user also has it's pros.

Thoughts?
-- Kevin