Re: Distributed foreign keys (was Re: Category Types)
Date: Thu, 26 Jun 2003 08:15:11 +0300
Message-ID: <3EFA815F.9050109_at_atbusiness.com>
Bob Badour wrote:
>>assignment. In particular I'm no fan of this sentence from the manifesto
>>(page169 2nd Ed):
>> "Note that the overall result [of a multiple assignment] might be
>>unpredictable if the target variables T1, T2, ..., Tn are not all
>>
>>
>distinct"
>
>I think the 'in parallel' part is a bad idea. The compiler should be able to
>determine which actions can proceed in parallel simply from the DAG it
>builds for the expression.
>
>
I think the history of this parallel stuff is that in first ed of
Manifesto they had constraint verification
at end of transaction and then came to the conclusion that it would be
too hard to implement.
There are still situations where you need to do several operations "at
once" so that
db remains in a valid state at statement boundaries. Hence introduction
of parallel statements.
Not 100% sure, but that's my understanding.
Lauri Received on Thu Jun 26 2003 - 07:15:11 CEST