Re: selecting all records where a column is null

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От Scott Marlowe
Тема Re: selecting all records where a column is null
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Msg-id Pine.LNX.4.33.0206201419300.8770-100000@css120.ihs.com
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Ответ на selecting all records where a column is null  ("Elmshauser, Erik" <erike@pbgnw.com>)
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On Thu, 20 Jun 2002, Elmshauser, Erik wrote:

> Hi, I am trying to select every record from a table where a specific
> column does not have a value in it yet.  Is there a way to express that
> in a SQL statement?  Here are the few I tried:
>
> select * from table where field;
> select * from table where field = '';
> select * from table where field = NULL;
>
> and some other stuff the is way more broken.  I have flipped through the
> docs a bit but I haven't found anything useful yet.  If someone could
> point me to the right place in the docs or give me an example of a
> select that will do this I would be very grateful.

Try

select * from table where field IS NULL;

--
"Force has no place where there is need of skill.", "Haste in every
business brings failures.", "This is the bitterest pain among men, to have
much knowledge but no power." -- Herodotus




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