SQL Update using Variable Field

Hi,
      I can't find anywhere where it says I can't do this, but I'm not sure
how to achieve it.  I have a file with a sales amount for each month
(SAL01,SAL02...SAL12). I want to use an SQL statement to zero the month in
all records before updating it. So, instead of UPDATE SALES SET SAL01 = 0,
I can replace SAL01 with the field for the appropriate month. Is this kind
of thing possible? I found where you can use variables for the order by
clause, but nothing like this.

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Terri Harteau
Felker Brothers Corporation
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"There's no point in being grown up if you can't be childish sometimes."
- Dr. Who
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