Update all records

I need to iterate the records somehow and update each record separetly.

For example i want to decrease each column# ordertotal for 10% while they have different values. One can be $100, another $200, 120, 140$ etc. etc.

Thanks!

Are you looking for a SQL query?

Update TableName
Set OrderTotal = OrderTotal * .9

The above statement will decrease the OrderTotal column of all records in the table by 10%.