Its just use a constraint then? there´s no problem id two sessions decrease the number, and this number goes to less then or equals as zero? I´m programming with php.
Thanks 2007/12/3, Cesar Alvarez <[EMAIL PROTECTED]>: > > What are you programing with?. > are you using npgsql? > > Regards Cesar Alvarez. > > Hi everyone, > > > > I would like to know how can i do a simple transaction for this > > situation: > > > > I have n products in certain row of a table. When the user buys a > > product, the quantity of this product will be decreased. The user can > > only buy a product that has a quantity n > 0. This means that when the > > user send the product confirmation to the system, the bd will decrease > > the product quantity with a transaction if the number of product in > > stock is greater than zero. > > > > > > Did anyone knows how can i do that with postgre? > > > > Thanks a lot. > > >
