Re: NULL saves disk space?

>Do I save disk space by having them as NULL instead of FALSE? So my >application would have conditional code for NULL and TRUE, instead of >FALSE and TRUE.

The short answer:
do not even think about it.

NULL has a well defined meaning within SQL: "we do not know the
value", with "well defined" being something totally different from
"intuitive".

With "using NULL as false" you woud get:

select whatever from yourtable where not (booleancolumn = true )

would result in ....wait for it .... zero rows.

Because "NULL" is not "not =" to true.

There is no potential diskspace saving in the world that could be
worth those troubles.

Harald

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Harald Armin Massa     www.2ndQuadrant.de
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