Re: database integrity
From: Kenneth Downs <knode.wants.this_at_see.sigblock>
Date: Fri, 20 May 2005 07:34:29 -0400
Message-ID: <nmu0m2-gna.ln1_at_pluto.downsfam.net>
>
>
> You have preempted my second question
> in regard to data integrity.
>
> Q2: Is data integrity a static or a dynamic thing?
>
> A2: Data integrity is a dynamic, because the world is dynamic.
> Rules change, data ages. Without some form of proactive measures
> examining and reviewing the integrity of a database, degradation of
> integrity may be expected to occur as change progresses.
>
>
> How do ppl out there guard against loss of integrity due
> to change? My approach has been to attempt to identify
> and itemise the elements of change, and for each item of
> change determine if data elements are effected, and then
> identify exhaustively these data elements, then "correct" them.
>
> This is another example of why I favour the establishment
> and use of an automated data integrity exception register.
>
Date: Fri, 20 May 2005 07:34:29 -0400
Message-ID: <nmu0m2-gna.ln1_at_pluto.downsfam.net>
>> >> One question on my mind is the change in rules over time. Do we say: >> >> 1. Data is valid if it adheres to all existing biz rules, OR: >> 2. Data is valid if it adheres to rules that were in force when it was >> inserted or updated.
>
>
> You have preempted my second question
> in regard to data integrity.
>
> Q2: Is data integrity a static or a dynamic thing?
>
> A2: Data integrity is a dynamic, because the world is dynamic.
> Rules change, data ages. Without some form of proactive measures
> examining and reviewing the integrity of a database, degradation of
> integrity may be expected to occur as change progresses.
>
>
> How do ppl out there guard against loss of integrity due
> to change? My approach has been to attempt to identify
> and itemise the elements of change, and for each item of
> change determine if data elements are effected, and then
> identify exhaustively these data elements, then "correct" them.
>
> This is another example of why I favour the establishment
> and use of an automated data integrity exception register.
>
If we consider a database to be a record-keeping system, then data that is
valid when committed remains valid forever, it is a record of some
transaction that was valid when performed.
When the rules change the old data remains valid. To change it is to alter
(falsify is a stronger word) records.
-- Kenneth Downs Secure Data Software, Inc. (Ken)nneth_at_(Sec)ure(Dat)a(.com)Received on Fri May 20 2005 - 13:34:29 CEST