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I need help with I think should be a pretty simple query.


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#1 Gmunky

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Posted 12 September 2006 - 03:53 PM

How do i write a query that outputs all the records when a specified attribute is null?
for instance, if the table looks like this:
_______________________
studentID | phone            |
--------------------------|
1          |111-111-1111  |     
2          |222-222-2222  |
3          |                      |
4          |                      |
---------------------------

I want to output all the studentIDs with no phone numbers.

i tried SELECT studentID WHERE phone is NULL; but i get an empty set.
Thanks for all your help!

#2 .josh

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Posted 12 September 2006 - 03:54 PM

how about:

select studentID from table where phone = ''
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#3 Gmunky

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Posted 12 September 2006 - 03:56 PM

ha. thanks!

#4 Gmunky

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Posted 12 September 2006 - 03:59 PM

ok. how about if I want to output the studentID's that are NOT null?

#5 obsidian

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Posted 12 September 2006 - 04:00 PM

SELECT * FROM tableName WHERE studentID IS NULL;

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#6 .josh

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Posted 12 September 2006 - 04:07 PM

ok. how about if I want to output the studentID's that are NOT null?

select studentID from table where studentID != ''
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