Re: Ordering dependency problem

On 18 Jan 2002 11:02:45 -0800, 71062.1056_at_compuserve.com (--CELKO--) wrote:

>The reason I say that the adjacency list model (i.e. (employee, boss))
>is not normalized is that when an employee changes, the change can
>affect more than one row wher he is a boss. A normalized database
>stored one fact, one way, one place, one time.

This is not a problem with the adjacency list model, but with storing the adjacency list in the same table as the data themselves (and using names as PK's).

There is nothing wrong in having to change all the records of the subordinate. After all, for each of them a fact changes - the name of their boss. If this is because the boss changes his name, it is bad. If it is because he is fired, it is OK.

-- 
Nis Jorgensen
Amsterdam

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