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T-SQL: Why does "select null or 1" elicit a syntax error?

Posted on 2010-11-16
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Last Modified: 2012-08-13
I'm trying to manually test to see if part of my WHERE clause will work correctly:
... and (ColA=1 or ColB is null) ...
and it's likely that ColA will be null.

Question: HOW can I test this MANUALLY "at the console" with a simple select statement?

I tried something like this and doesn't work... it returns a syntax error:
select null or 1
to illustrate ColA being null and ColB NOT being null.   I want to "prove" this will evaluate TRUE (null or TRUE => TRUE).
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Question by:ZuZuPetals
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cyberkiwi earned 500 total points
ID: 34151111
this is a query that tests your condition (mock)

select 1
where (null = 1 or 1 is null)

here if the where condition is true it returns 1 otherwise no result
see cola replaced by null and colb by 1
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by:ZuZuPetals
ID: 34151152
Ah, that helps.  I was trying to do my "console" statement in the same form as
select 2+2
Guess that's not valid SQL!
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Expert Comment

by:cyberkiwi
ID: 34151216
select 2+2 does work
But
select (null=1)
for example is hanging.. it returns a condition, but what is it doing with it?
So we make a where clause out of it
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