I tested both of these truth tables for the underlined conditions:

false AND null

and

true OR null

because I wasn't sure about the behavior here. The programmer in me said short circuiting might work, while the ternary logician in me misremembered a NULL result in both of those conditions. On both my 2k8 and 2k5 installations, I only got the OR behavior to match the article. Is there a setting I'm missing? I tried this with ansi_nulls both off and on with the same result.

using this SQL:

if(1=1 or 1=null)

print 'test passed'

else

print 'test didn''t pass'

if(1=0 and 1=null)

print 'test passed'

else

print 'test didn''t pass'

My output is:

test passed

test didn't pass