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I fell into the NULL void (so to speak) When I said that NULL = NULL
evaluates to false, it should be "it does not evaluate to TRUE". That
blasted three value logic. It actually evaluates to NULL. In this
world, the opposite of TRUE is not FALSE; it is (FALSE or IS NULL) :>.
AND the opposite of FALSE is not TRUE; it is (TRUE or IS NULL).
The use of NULL in an "IN" clause (at least in Oracle) does seem to be
meaningless, but NULL is a valid parameter in Oracle FUNCTIONS and
PROCEDURES.
The argument
In article <u7wvyflmfu.fsf_at_ebi.ac.uk>,
Philip Lijnzaad <lijnzaad_at_ebi.ac.uk> wrote:
> "James" == James Lorenzen <james_lorenzen_at_allianzlife.com> writes:
>
> is that 'known to unknown', or 'unknown to be known', or 'unknown to
> be unknown' ... :-)
> NULLs are, of course, useful but ocasionally dubious.
(very tricky)
All of this NULL thinking makes my brain hurt. ;)
James
--== Sent via Deja.com http://www.deja.com/ ==-- ---Share what you know. Learn what you don't.--- Received on Tue May 11 1999 - 13:40:35 CDT