query using 'is null' and ' or 'is not null' with checkboxes

[Guest]

Lets say my table has fields 'text name', 'text class', 'check box enrolled'
When I create a query with 'criteria' in the check box section stating 'is
not null' this works fine, I get my answser, when I use 'is null' I get
nothing

I'ts been a few years since I've had to use access, maybe I'm unaware of
some upgrades, and new tricks....any help
Cheryl

 

[John W. Vinson]

Lets say my table has fields 'text name', 'text class', 'check box enrolled'
When I create a query with 'criteria' in the check box section stating 'is
not null' this works fine, I get my answser, when I use 'is null' I get
nothing

That's because a Yes/No field cannot ever be NULL: it can be true or false,
only.

You can use an Integer number field with a checkbox as a control, storing -1
for True, 0 for False, and null for undetermined.

John W. Vinson [MVP]