Thanks for both your reply. Dave, I got what u reply done before this. Just the problem happen when i'm using UNIQUE as what Jim told me. I'd run some test and found that the UNIQUE index file will not be updated if I've deleted the record that it was taking action at. It will read the read the kept reading the one that has already been marked for deletion. I've found a way to encounter the problem is that if I pack and reindex after i made a deletion, the UNIQUE will read the new record. Any idea for this?

I'm not very sure of SQL select yet.

Gan