RE: Interesting question and debate on ddl tables with date fieldsthatwill not always have a value

Anyway, not everyone agrees with your blanket assessment of nulls

Agreed. Not everyone agrees with my assessment of Bush either, but
that's ok. :-)

No, just about every database scientist whom I've read would insist on

a

flag that indicates the status of the employee rather than relying on
the NULL value to give you any more information than the fact that you
don't have a termination date.

Not arguing that you should rely on the null value to indicate that the
employee isn't terminated, rather that you should use the null value to
indicate that you don't have a value for the terminated date. Even with
a flag to indicate the status of the employee what value do you put into
the terminated date? You can argue that the value is irrelevant since
the employee isn't terminated, but you still need a value. Hence, use
null. :-)

-Walden