<div>
Try this:<br />
<br />
UPDATE YourTable<br />
SET ColC = ColA - ColB
</div>


Try this:

UPDATE YourTable
SET ColC = ColA - ColB

<div>
I have already tried that here is the message that I get, maybe it will help.<br />
&nbsp; <br />
Invalid operator for data type. Operator equals subtract, type equals varchar.<br />
<br />
<br />
Frank<br />

</div>


I have already tried that here is the message that I get, maybe it will help.
 
Invalid operator for data type. Operator equals subtract, type equals varchar.


Frank


<div>
This means that one of your columns (either ColA or ColB) is a varchar.
</div>


This means that one of your columns (either ColA or ColB) is a varchar.

<div>
All three columns are varchar.
</div>


<div>
<div class="content wysiwyg-content">
Hi,<br />
<br />
I would like to do the following operation.<br />
<br />
Col A- Col B and then put result in Col C. &nbsp;All the columns are from the same table.<br />
<br />
The values are numeric it would be something like this:<br />
Col A - Col B = Col C<br />
&nbsp; &nbsp; 11 - 7 &nbsp; &nbsp; &nbsp;= 4<br />
<br />
TIA,<br />
Frank
</div>
</div>


Hi,

I would like to do the following operation.

Col A- Col B and then put result in Col C.  All the columns are from the same table.

The values are numeric it would be something like this:
Col A - Col B = Col C
    11 - 7      = 4

TIA,
Frank

How to subtract data in columns

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