IsValid refers to the data type. It is not solely to test for the presence of a related value.

From the documentation:

> Returns 0 (False) if:
>  • A record contains an invalid value because of a field type mismatch (text in a date field, for example)
>  • FileMaker Pro cannot locate (temporarily or permanently) the related table in which the referenced field is defined
>  • A field has been deleted from a related table, and therefore the references to that field in the parent table are invalid
> Otherwise, it returns 1 (the data is valid).

So the circumstances where you might get a wrong answer is if you have an invalid data situation.

Best not to get into the habit.

j.

On Jun 22, 2011, at 7:16 PM, Tim Mansour wrote:

> On 23 June 2011 08:02, Jonathan Fletcher <[log in to unmask]> wrote:
>> Not IsValid. That may give you a wrong answer under certain circumstances. The way described prior in this thread is correct.
> 
> Can you expound, Jonathan?
> 
> 
> -- 
> Tim Mansour <[log in to unmask]>
> Neologica Print & Promotions ABN 63 904 335 408
> Certified FileMaker 10 Developer
> PO Box K1163 : Haymarket NSW 1240
> Mobile 0405 500 846




--
Jonathan Fletcher
FileMaker 9 & 10 Certified Developer

Fletcher Data Consulting
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