[postgis-devel] Re: [postgis-users] create tables smarter

[Tom Lane]

"Paul Ramsey" <pramsey at cleverelephant.ca> writes:
> Very cool. Interesting limitation though:
> ... However, this information must be capable of being
> packed into a single non-negative integer value for storage in the
> system catalogs"

> Could make support for srid values tricky, to say the least...
> currently it looks like we can do it, but it would requires some
> constraining of spatial_ref_sys.

The argument that carried the day for implementing it like that was
that the stored typmod could just be an index into a table, lookup
key in a catalog, etc.  So in principle you can associate as much
data as you want with any column.

IIUC, setting up such a catalog entry is pretty much what
AddGeometryColumn does already --- so in some sense, the user-defined
typmod stuff would just be pretty syntactic sugar for a call to
AddGeometryColumn.

			regards, tom lane