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Wildhoney · 02-26-2008, 05:25 PM

Something like the following? The @fValue variable is the amount to deduct.

sql Code:

UPDATE
    cash,
    (
        SELECT
            @fValue:=1.99,
            @fCash:=(cash - @fValue),
            @fCash:=IF(@fCash > 0, cash - @fValue, 0)
        FROM
            cash
        WHERE
            id = 1
    )
    AS fCash
SET
    cash = @fCash
WHERE
    id = 1

02-26-2008, 05:25 PM	#2 (permalink)
Wildhoney La Vida es Sueño Join Date: Sep 2007 Location: Oldham Posts: 2,280 Thanks: 90	Something like the following? The `@fValue` variable is the amount to deduct. sql Code: UPDATE cash, ( SELECT @fValue:=1.99, @fCash:=(cash - @fValue), @fCash:=IF(@fCash > 0, cash - @fValue, 0) FROM cash WHERE id = 1 ) AS fCash SET cash = @fCash WHERE id = 1 __________________ The man who comes back through the Door in the Wall will never be quite the same as the man who went out.