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

[Karsten Hilbert]

> >> 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.
>
> just wondering how a trigger would "check" that the external_id value 
> conforms to whatever is in the column 'regexen' …
>
> would it require some kind of casting of what is in the regexen and 
> converting it into a function wherein the value of the external_id must 
> compute as TRUE?

It would check the column value against the regular expression and see whether 
there's a match.

Karsten