Re: Does Codd's view of a relational database differ from that ofDate&Darwin?[M.Gittens]

Jan Hidders wrote:

>
> Another small thing is updating primary keys. If a primary key has
> accidentally been entered wrong and you want to fix that with an update
> then it is usually not possible to simply update it, and the problem
> gets even worse if it is also refered to by foreign keys. In an ER model
> this is a non-problem.
>

like a few other people (i suspect we are a minority), i think of 'update' as a sugaring or shortcut. ignoring transaction or concurrency issues, is there any logical difference between 'update' and the combination of 'delete-insert'? (granted the latter implies an operator sequence which is why i ignore concurrency issues.)

when i hear the above complaint, i'm inclined to think that it is just an example of the dead-ends that can appear when taking shortcuts. maybe it is a 'small thing', but i'd say the complaint is bogus. maybe this makes me a purist!

paul c. Received on Thu Jul 07 2005 - 21:49:54 CEST