Uniqueness in calculated fields

[Mark Stevens (Steve) Willis]

Hi, all!

In a standard key field that has been indexed, I can enforce  
uniqueness on the contents to ensure that duplicate keys cannot exist.

There is no inherent capability within FMP to ensure uniqueness upon a  
calculated key.

Is there a technique or custom function that can perform uniqueness  
enforcement on calc fields?

Thanks!

Steve
--
Steve Willis
stevewillis at mac.com

An artist is not paid for his labor but for his vision.
                                  James McNeill Whistler


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[Corn Walker]

On Nov 7, 2009, at 2:15 PM, Mark Stevens (Steve) Willis wrote:

> In a standard key field that has been indexed, I can enforce  
> uniqueness on the contents to ensure that duplicate keys cannot exist.
>
> There is no inherent capability within FMP to ensure uniqueness upon  
> a calculated key.
>
> Is there a technique or custom function that can perform uniqueness  
> enforcement on calc fields?

Make the calculation field an auto-enter calculation instead, then  
apply your uniqueness constraint. This works in most cases.

Cheers,
-corn


Cornelius Walker
The Proof Group
http://proofgroup.com/


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