Thanks for your feedback guys.
naturally doesn't track history very well. I want to implement Type II, but
the data in the source systems has its issues, hence my concerns.
especially once it's been reported on. However, the business is still fairly
lots of Access and Excel apps extracting and manipulating data for reporting.
"Peter Nolan" wrote:
> Hi Wreck,
> you are entering 'religious territory' ground......
>
> There are two religions here:
> 1. Go back and correct data 'known to be incorrect'.
>
> 2. Retain data known to be incorrect and enter new transactions which
> update the DW such that it now represents the data 'known' to be
> correct. (Which is really just 'thought to be correct now'.)
>
> I come down in the camp of retain the incorrect data and enter new
> transactions such the data is now set to the 'thought to be correct
> value'. In your case, the account would be 're-opened' and it would
> occur as 're-opened'.
>
> Why?
>
> Because going back and updating data is a very slippery slope. Where
> does it end? And if decisions were made against data that was presented
> at a certain point in time and then the underlying data is 'corrected'
> and people come along to review those decisions and the data says
> 'these decisions are not well founded on the data' what does one do?
>
> One must remember that data is never, ever 'true' or 'correct' it is
> only ever 'thought to be correct/true' which means that data that we
> have realised is incorrect and we now believe to be true has the same
> likelyhood of being incorrect as the data we just changed.....
>
> Whereas, if we retain the fact that we found data to be incorrect and
> we enter transactions to place new transactions to correct that data we
> can see the information on which decisions were taken at the time. We
> can also see how often data is being corrected.....perhaps there are
> underlying issues for a high rate of data corrections occurring such as
> lack of proper training in the call centers taking calls and entering
> data? It happens....
>
> In some cases it is a legal requirement not to correct historical data.
> For example, in most countries it is illegal to update the financial
> statements of a company after the close of the annual accounts....yet
> clearly there have been some very 'incorrect' entries in the financials
> of some very large companies over the last few years.
>
> Best Regards
> Peter Nolan
>
www.peternolan.com >
