I think I see your point, although at first reading I was a bit dumbfounded.
Conversation via email can be so difficult. At first it sounded like you
were surprised I was actually trying to design my application around business
rules! Further, that it was going to be up to my users, not my application,
to enforce our business rules. Finally, it sounded like you were saying that
if any Access features proved helpful in this task, it would be purely
accidental!

I believe you were actually saying that, right offhand, there is nothing I
can do to the structure of my tables or their relationships to prevent
unwanted records of the sorts I described. Rather, these illegal operations
must be prevented by traps in my code or by using data validation rules.

A perhaps easier example would be in retail sales. Let's say we offered a
product for sale with the condition: limit one per customer. This would mean
that for any instance of this product in the OrdersProducts join table, the
Quantity would have to be limited to 1 each. Also, we would have to prohibit
multiple separate instances of the same product on the same order. Further,
we would have to prevent multiple orders for the same product from the same
customer. These kinds of constraints would not be enforced through table
structure, except to the extent of making sure we placed a field to our
Products table for flagging such products.

Regards,
OldBlindPew

"Jeff Boyce" wrote:

It sounds like you are describing the "business rules" of your operation.
It wouldn't matter if you were using Access or Excel or paper and pencil,
those rules would apply (e.g., no customer carries more than one GL policy).

I'm not aware of any built-in business rule enforcer in MS Access. I
believe you'll need to add the validation checks to enforce those rules.

In some of your situations, using a unique index on multiple fields could be
a way to use Access features to enforce your business rules ... but that's
just plain lucky! You'll probably need to figure out some edits/validation
tests for your form, to prevent the users from doing something your business
doesn't permit.

Good luck!

Regards

Jeff Boyce
Microsoft Access MVP

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Disclaimer: This author may have received products and services mentioned
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does not constitute endorsement thereof.

Any code or pseudocode included in this post is offered "as is", with no
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You can thank the FTC of the USA for making this disclaimer
possible/necessary.

"oldblindpew" wrote in message
...
CertsPoliciesID is autonumber and therefore the unique primary key for the
junction table. A unique index on the combination of CertID and PolicyID
would prevent redundant Cert/Policy pairs.

But I am also concerned with redundant Agreement/Policy pairs. It is
acceptable for an Agreement to have more than one Cert, but not that the
same
Policy should appear on more than one of their Certs. Enforcing
Cert/Policy
uniqueness alone doesn't prevent this, and the uniqueness of the
CertsPoliciesID key adds nothing.

Similarly, I am concerned to prevent improper combinations resulting from
policy types. No Insured party is going to carry two General Liability
Policies. If we try to attribute two different GL policies to the same
Insured, either by assigning the two policies to the same Cert, or by
assigning them to two different Certs that are in turn tied to the same
Agreement, something is wrong.

Thanks,
oldblindpew

"Piet Linden" wrote:

You could create a unique index on the combination of (CertID,
PolicyID) in the CertsPolicies table. Nothing wrong with that. Then
if your CertsPoliciesID is an autonumber and set to be unique, you
should have everything, right?
.



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