Re: [Gnumed-devel] ID issuers, types, and validation

[Busser, Jim]

On 2013-07-28, at 8:35 PM, Jim Busser <address@hidden> wrote:

>>> One sane approach would be to define a (number of) regular
>>> expression(s) with each external ID type:
>>> 
>>>    dem.enum_ext_id_types.regexen text[] default NULL
>>> 
>>> and have INSERT/UPDATE triggers on dem.lnk_identity2ext_id
>>> check that.

What about a praxis

1) modifying their GNUmed schema post-hoc, to add local constraints
2) keep track of such modifications, so as to be able to drop the extra local 
constraints at the time of wanting to upgrade their GNUmed db
3) when wanting to upgrade their local db, they adjust their schema to match 
what the GNUmed bootstrapper / updater requires
4) following the update, the praxis re-applies their local constraints

The above would not work the other way around. For example, if a praxis *drops* 
base GNUmed constraints, and inputs data that GNUmed would normally refuse, 
then they will be unable to re-apply the constraints because existing data will 
be incompatible.

Doing it the other way around however -- making the data locally more 
restrictive -- should not be a problem should it?

-- JIm