On Aug 3, 9:56 pm, Jerry Whittle
wrote:
I once had the 'pleasure' of trying to fix a problem where a company was
bought by another and, guess what, the employee numbers were all changed!
Since they didn't have Referential Integrity enabled (actually couldn't as
there were some orphaned records) couldn't use Cascade Update.

I'm a firm believer in autonumbers for PKs. If it doesn't have a meaning,
you won't be tempted to change it.

Now consider the scenario where two companies use auto-increment
values for their personnel data then those companies merge...

Jamie.

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