>>That means that there is a difference between using something like "prov_id = providers.iid" and "pr_address.prov_id = providers.iid"????
>
>You must exactly match what is there. You'll need a tag on prov_id.

Hi Craig,

I probably should've been more explicit in my question. The differences between something like "upper(a + b)" and "upper(a) + upper(b)" are obvious. The doubts I have is whether including the alias in the expression affects it at all. That's why I asked. Currently my tag in pr_address is simply on "prov_id", but in the sql, I refer to it as pr_address.prov_id (now it has an alias).

Does that make a difference? Also, what about aesthetic differences? For instance "UPPER( A )" vs. "upper(A)". Both are functionally equivalent and should be interpreted exactly the same way by vfp, but one is all in caps and has spaces around the 'a' while the other isn't.

Thanks very much for you patience and also thanks for the explanation on the 3-table joins.

alex