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>>>>>Bear in mind that the DELETED() status has nothing to do with the uniqueness of a candidate or primary index. In any incremental key situation, you have to search all your table whether or not the records have been deleted.
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>>>>PMFJI but in addition, even if you should check the deleted records, a simulataneous add by two users will also give the same behavior.
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>>>I agree. Tying this into an earlier thread about unique keys, I don't even try to use sequential numbers unless forced to. I like to use GUIDs as primary (unique) keys.
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>>You bring up a question in my mind that I've had for awhile. Are there any *real* benefits to using unique or candidate keys. I've yet to come up with anything that outweighs the annoyances.< s >
>
>Absolutely there are. To name two (and there are others) that apply to VFP:
>
>1) Normalization. You need a unique key that will never change.
>2) Scalability. SQL Server and Oracle DEMAND unique, primary keys.
>3) Conflict. A unique violation may alert you to other errors in data mgmt.
PMFJI, but doesn't referential integrity depend on primary key as well??
Just my $0.02
Rex
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