M, convention has it that only referential
constraints that reference candidate keys are called foreign keys whereas
SQL allows its FOREIGN KEY to reference any columns declared as unique (ie
may be a super key rather than a candidate key).
--
David Portas
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<[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]
>> Gregory Stark <[EMAIL PROTECTED]> writes:
>>> I'm not sure if there's a fundamental reason why there has to be an
>>> index that
>>> exactly matches the foreign key or not -- offhand I can't think of one.
>>
>> The reason why is that t
) algorithm. If the CRC is identical for the
> extracted record and the most recent row in the master table, then we
> ignore the extracted record. We don't need to check every column to be
> certain that the two rows match exactly."
>
Be careful with Kimball. Read him to
