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Home -> Community -> Usenet -> c.d.o.misc -> Re: NULL versus empty string
"David Wall" <d.wall_at_computer.org> wrote:
>
> <quote>
>
> Do not use null to represent a value of zero, because they are not
> equivalent. (Oracle currently treats a character value with a length of
> zero as null. However, this may not continue to be true in future
> releases, and Oracle recommends that you do not treat empty strings the
> same as nulls.)
Yes, isn't that clever. Does that mean they recommend that you do not use their products?
> Any arithmetic expression containing a null always
> evaluates to null. For example, null added to 10 is null. In fact, all
> operators (except concatenation) return null when given a null operand."
Bull. The 'or' and 'and' operators can return true and false, respectively, if given a null operand assuming the other operand is true or false, respectively.
> </quote>
Xho
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