Re: Pizza Example

From: Anthony W. Youngman <>
Date: Sun, 18 Apr 2004 23:46:30 +0100
Message-ID: <>

In message <>, Jerry Gitomer <> writes
>>>You still persist in believing that nonsense about "losing information"
>>>by decomposing data? This just reflects your ignorance of how an RDBMS
>>>works, and it is time you rectified that.
>> It happens in the scientific world all the time. Why should the data world
>> be any different?
>Because data integrity standards are much more rigorous in the commercial
>world than in the world of science. For example, it is not at all unusual
>for a scientist to be pleased that 90% of the sample data collected on a
>project is good data and only 10% is bad data that will be discarded
>and/or ignored. When it comes to dealing with payroll data, payables and
>receivables, and inventories anything less than 100% is unacceptable and
>checks and balances are built into commercial systems to insure that all
>of the data is collected and that, before it goes into the database,
>all is valid.

Who gives a sh*t about "standards" when there's a scientific law that says you can't do it?

I do appreciate what you're saying, about how database integrity standards are rigorous, but the scientific equivalent of what you propose is not separating the results into "90% good, 10% bad"; it is claiming that you have just invented a perpetual motion machine. In the real world, IT CANNOT BE DONE. PHYSICS FORBIDS IT.

The standard version of the law is basically "in any closed system, any change will increase entropy". A physicist would also recognise and accept the following paraphrase - "in any closed system, any change will destroy information" - the terms "entropy" and "information" are recognised as a sort of opposite (I can't remember the detail, it's too long ago).


Anthony W. Youngman - wol at thewolery dot demon dot co dot uk
HEX wondered how much he should tell the Wizards. He felt it would not be a
good idea to burden them with too much input. Hex always thought of his reports
as Lies-to-People.
The Science of Discworld : (c) Terry Pratchett 1999
Received on Mon Apr 19 2004 - 00:46:30 CEST

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