Re: back-sql problem: RDBMS with multi-value keys represented using LDAP?

[Dmitry Kovalev <mitya@seismic.geol.msu.ru>]

Hello, Heiko!

Heiko Nardmann wrote:

> I am facing the problem to represent an RDBMS where several tables
> have multi-value keys, i.e., keys which consists out of more than one
> column/value.
>
> The problem is that I don't know what to insert into e.g. the RDBMS
> mapping
> table ldap_oc_mappings as the values for keycol.
>
> Anybody an idea how to proceed here?

two ways:
1) patch back-sql accordingly
2) make a single-valued index to serve as primary key

>
> Do I have to create an artificial index here for every multi-value-key
> table
> as a workaround?

this is a way #2 :)
BTW, I think it is generally better in practice anyway. Multivalue primary
keys are fine on design stage, they are fine as integrity checks, but
artificial integer key is generally faster in joins etc.

I'm not trying to say this is the way it _must_ be, but anyway, this is the
way it is in back-sql - this removes so much complexity that I considered
it not a big constraint. And one more automatically maintained column is
not a big problem IMHO...

WBW, Dmitry