On 08/25/2015 01:56 PM, John R Pierce wrote:
> On 8/25/2015 1:42 PM, Gavin Flower wrote:
>> Account numbers are externally generated, and may potentially change.
>> Management might suddenly decide that they want to start using the
>> year the account started as the first 4 digits, or that the branch
>> code should be reflected in it, or something else. The database
>> should be protected from these arbitrary changes. Hence the
>> account_no is not a good candidate for a primary key.
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> such practices would raise total havoc on a traditional paper ledger
> accounting system as well as things like pending AR/AP where external
> companies will be referencing your account numbers.
Agreed, but it happens. When Lowes took over a local hardware
chain(Eagles) here in Washington state they moved very quickly on
changing the account numbers. The company I worked for who supplied
Eagles and then Lowes sat on a check for $22,000 that was sent to us in
error because the account numbers got switched. We called them when we
got the check, but it still took them six months to own up to it.
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--
Adrian Klaver
adrian.klaver@aklaver.com