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From:Chris W Date:March 15 2009 12:38am
Subject:Re: Fwd: avoiding use of Nulls
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Arthur Fuller wrote:
>  Exactly the point. Michael, NULL *is* information. It means "unknown" and
> that is in itself useful information. A common example:
> A new employee is hired but which department she will work in is unknown. So
> the data entry person enters all the known information and leaves the rest
> until it has been clarified.

In this case, you could have a table to link the employee to 
department.  If you didn't know what department an employee was going to 
be in, there would be no record in that table.  However I agree with 
Mike, why are you hiring someone if you don't know what they are going 
to be doing.  Also having the separate table to link employees and 
departments allows for a many to many relationship, so an employee can 
work in more than one department.  I'll leave the discussion for how bad 
an idea that is for another list :)

Chris W
Fwd: avoiding use of NullsArthur Fuller14 Mar
  • Re: Fwd: avoiding use of Nullsmichael14 Mar
    • Re: Fwd: avoiding use of NullsJohan De Meersman15 Mar
  • Re: Fwd: avoiding use of NullsChris W15 Mar