Re: VAT rate or VAT amount as a column?
Date: Sun, 06 Aug 2006 12:33:21 -0400
Message-Id: <18ihq3-v82.ln1_at_pluto.downsfam.net>
Emily Jones wrote:
> Your suggestion destroys normalisation.
As I said before, many views are denormalized. What is the difference
between a system-controlled view and a system-controlled derived column in
a table?
>
Yes. In answer to your original question I suggested a trigger. Our
conversation since then has fleshed out my suggestion. That's really about
it from my side. Also, I believe you've gone another track, so at this
point we really are just chatting about theory.
> And who said anything about a trigger? That seems to be your idea.
>
> Emily
>
> "Kenneth Downs" <knode.wants.this_at_see.sigblock> wrote in message
> news:c6fhq3-r32.ln1_at_pluto.downsfam.net...
>> Emily Jones wrote:
>>
>>> A view isn't the same as a base table though is it? Materialised or not.
>>
>> Right.
>>
>> My point is that if we allow system controlled derived data, and we trust
>> the values we are given because we trust the db server, what does it
>> matter
>> if we put the values in a view (materialized or not), or into the base
>> table? Further, putting them into the base table is just plain simpler
>> and
>> more convenient.
>>
>> The trigger is the mechanism that lets us accomplish a system-controlled
>> derived value, and to put it where it is easiest to use: directly into
>> the base table.
>>
>>>
>>> "Kenneth Downs" <knode.wants.this_at_see.sigblock> wrote in message
>>> news:q0heq3-ghe.ln1_at_pluto.downsfam.net...
>>>> Emily Jones wrote:
>>>>
>>>>>
>>>>> I thought a table with a derived column in it ISN'T normalised.
>>>>> Functionaly dependent not on the Primary Key, or something. No?
>>>>>
>>>>>
>>>>
>>>> Correct. But neither is the data in many views. Both are system
>>>> controlled
>>>> (if you go triggers) so whatever theory allows views allows the
>>>> materialized columns.
>>>>
>>>> --
>>>> Kenneth Downs
>>>> Secure Data Software, Inc.
>>>> (Ken)nneth_at_(Sec)ure(Dat)a(.com)
>>
>> --
>> Kenneth Downs
>> Secure Data Software, Inc.
>> (Ken)nneth_at_(Sec)ure(Dat)a(.com)
-- Kenneth Downs Secure Data Software, Inc. (Ken)nneth_at_(Sec)ure(Dat)a(.com)Received on Sun Aug 06 2006 - 18:33:21 CEST