Re: Can a boolean ever be set to null?

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If I remember correctly, the Byte is the datatype that takes the least amount
of bits to store, which struck me as odd... you'd think a boolean would be a
single bit, either 0 or 1, right? apparently that's not the case though. A
boolean actually takes more bits to store than a Byte, which can be one of
255 numbers.

So I would think, based on that, that there would be plenty of room in
memory to store whether a boolean would be true, false, or null.

The workings of bits is way beyond me, but a boolean takes more memory to
store than 0-255, for whatever reason.

--
Jack Leach
www.tristatemachine.com

"I haven't failed, I've found ten thousand ways that don't work."
-Thomas Edison (1847-1931)



"Dirk Goldgar" wrote:

"JimBurke via AccessMonster.com" <u49905@uwe> wrote in message
news:987adb4854b40@xxxxxx
Does Access not allow
Null for a boolean because it only examines one bit when it's dealing with
boolean fields? Just curious as to why they can't be Null. That's the only
reason I can think of.


I'm not sure, but I suspect that all the boolean fields in a table may
actually be store in a block of bits, with one bit per field. This is
purely conjecture, but it would be a space-saving measure. In such a case,
there would be no way to indicate that the field is Null.

--
Dirk Goldgar, MS Access MVP
www.datagnostics.com

(please reply to the newsgroup)

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