Re: The C in ACID

From: paul c <toledobythesea_at_oohay.ac>
Date: Mon, 21 Aug 2006 17:26:14 GMT
Message-ID: <W0mGg.445088$IK3.89751@pd7tw1no>

Paul Mansour wrote:
> paul c wrote:

>> My guess is that they're saying, to turn it around a bit, that the user
>> must not be allowed to pervert the dbms purposes of A,I and D.  And that
>> the user (or DBA) must tell the dbms how to test for Consistency.  It's
>> true that most systems usually require the user to tell them where a
>> transaction starts and where it finishes, but that's different from
>> telling it how.

>
> No, I don't think so. Explaining "Consistency" they write:
>
> "There is no system mechanism that prevents a user from entering a bad
> transaction, e.g., crediting the wrong amount to a bank account, or
> charging for an item that was not shipped."
>
> This is clearly referring to correctness, no?
>
> I was under the impression that the terminolgy and interpretation of
> ACID was pretty much agreed on, but this paper call the 'C' Consistency
> but appear to mean "Correctness."
>

I don't see a conflict. Perhaps you see a subtlety I don't. I consider the facts in a db correct if they are consistent with whatever constraints I've specified. If a user enters an untruth, there's nothing the dbms can do about it, unless it has been told, eg., with constraints, how to recognize certain lies.

p Received on Mon Aug 21 2006 - 12:26:14 CDT