[Koha-devel] Constraints on issues tables

[Chris Nighswonger]

On Wed, Oct 15, 2008 at 6:37 PM, Galen Charlton
<galen.charlton at liblime.com> wrote:
> Hi,
>
> I've found at least one Koha database that has multiple issues rows
> for the same item but different patrons.  This doesn't map well to the
> reality of loaning physical items, unless somebody's slipped in a Star
> Trek-style replicator feature, so I propose the following changes to
> constraints on the issues table:
>
> 1. Make itemnumber the primary key (and not null) - an item can be
> issued only once at any given time.
> 2. Make borrowernumber not null - a loan must be to a specific patron,
> and if the item is detached from the patron, there's no longer a loan.
> 3. Make renewals not null with a default value of 0.
> 4. Make issuedate not null - a loan must have started at a specific
> time; during a migration, if the issue date is not known, a made-up
> date can be supplied.
>
> Comments?

+1 here as well. I think relationships should be enforced in the db as
much as possible.

Regards,
Chris