Re: quick FK question

> As soon as fake value becomes normal business value problems might 
> arise. I'd personally better deall with NULLs because this is
> WIDELY understand concept both by developers and DBMSes compared
> to some specific value representing NULL, which is -1 for project1,
> 0 for project2 and 187913267532 for project3.

I agree. When I do data modeling, I personally never use a fake value 
for a simple missing value (as for reason of avoiding outer joins). But 
if multiple special values are needed in the design, and the developers 
agree, I could use e.g. -1 for generally unknown, -2 for lost, -3 for ... 
In this case, a single NULL couldn't satisfy the business need, and an 
additional column for these special values would be a little too wasteful.

Yong Huang


      
--
http://www.freelists.org/webpage/oracle-l

Other related posts: