Substract two field values to insert the result into a third value

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Hi,

I have this question, having two numeric values field1 and field2, i need field3 by default to be the difference between field1 and field , any idea??

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josjorge

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Sep 28th, 2009

Re: Substract two field values to insert the result into a third value

in one query:

MySQL Syntax (Toggle Plain Text)

UPDATE table SET field3 = field1-field2

I think this should work.

(everytime you update/change a value of field1/field2 you will have to do this query, mysql can't do this automatic..)

Last edited by Kruptein; Sep 28th, 2009 at 7:10 am.

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Oct 5th, 2009

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Re: Substract two field values to insert the result into a third value

or you can like be all cool and be like well find the column names and then do it with php $column1 - $ column2

SKANK!!!!!

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