# Related Sites > SqlCredit >  Part 5: Card, Vendor, Purchase

## rgarrison

*(This thread is associated with part 5 of the SqlCredit series published Friday, May 25th.)*

Please comment on any aspect of the latest entry in the SqlCredit series: the article, the latest changes to the database code, whatever.

----------


## rsocol

The way it is now (in part 5), I think there are some problems regarding the integrity of data stored in the PrimaryCardHolderID column. I see that you have not created the Account_PrimaryCardholder_FK foreign key, probably to allow entering a 0 for the PrimaryCardHolderID in the _AccountCreate procedure. A better design would be to allow nulls in this column and keep the foreign key. Why? Because now you can delete a card holder (with the CardholderDelete procedure) while it is the primary card holder for an account (as long as there is no card for that holder).

Razvan

----------


## rgarrison

My plan is to move this to an associative table mapping a Cardholder to an Account. This will get around all the ugliness that resulted from this weird two-way relationship between Cardholder and Account.

----------

