>>>>Hilmar,
>>>>I'm actually using "Not deleted()" as my tag instead of "deleted()". Is there any difference.
>>>>Yau
>>>
>>>I am not sure. But I think the index will be used anyway (which isn't always appropriate - see my FAQ), because the implicit condition, if you have SET DELETED ON, is ... AND NOT DELETED(). In other words, the index tag exactly matches the expression.
>>>
>>>If you need your index for other purposes (besides "optimization"), there are ways to avoid VFP using it.
>>>
>>>Hilmar.
>>
>>Using NOT in a tag means that Rushmore can't use it for optimization.
>
>Even if the expression explicitly says "NOT Something"? Perhaps, I am not sure.

I believe that's the case.

From the VFP8 help:
Using Rushmore Query Optimization to Speed Data Access

Indexing Effectively for Rushmore Query Optimization
Rushmore cannot take advantage of all indexes. If you use a FOR clause in the INDEX command, Rushmore cannot use the index for optimization. For example, because it contains a FOR clause, the following statement cannot be optimized:
INDEX ON ORDNUM FOR DISCOUNT > 10 TAG ORDDISC

Similarly, Rushmore cannot use an index created with a NOT condition. For example, the following expression can be optimized:
INDEX ON DELETED() TAG DEL

But this one cannot:
INDEX ON NOT DELETED() TAG NOTDEL