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From:Ashley Stars Date:August 21 2010 11:02am
Subject:Re: Performing subtraction between fields
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Ashish, Mark and off-list responders,

Thanks!

Ashish, is there a really good general reason not to store a computed
value? Searches will be done on this column. Searches like 'Please send me
the rows with the ten highest values of C.'

> Do you have a really good reason to store a computed value? It's only
> useful
> if you will perform a search on the column, else you could just do the
> subtraction when you SELECT columns A and B.
>
> - Ashish
>
> On Sat, Aug 21, 2010 at 11:55 AM, <b@stripped> wrote:
>
>> Hello,
>>
>> For simplicity's sake, let's say I have three fields, A, B and C, all
>> of which are integers. I'd like the value of C to be equal to A less B
>> (A-B). Is there a way I can perform this calculation? I'm guessing it
>> would happen when I INSERT a row and specify the values for A and B.
>> Feel free to direct me to the fine manual I should have read.
>>
>> Thank you.
>>
>>
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>>
>>
>


Thread
Performing subtraction between fieldsb21 Aug
  • Re: Performing subtraction between fieldsMark Goodge21 Aug
  • Re: Performing subtraction between fieldsAshish Mukherjee21 Aug
    • Re: Performing subtraction between fieldsAshley Stars21 Aug
      • Re: Performing subtraction between fieldsAshish Mukherjee21 Aug
        • Re: Performing subtraction between fieldsDan Nelson22 Aug
  • Re: Performing subtraction between fieldsChris W21 Aug