I'm trying to show the result of an show aritmetic exoression result WITHOUT saving to the table until I click a sve control button.
I would be very greatfull for any type of help.
There are several ways but it depends on the context of your question which one to use..
One way is to create an unbound textbox then set its Control Source property to the expression.
When you run your save event procedure the reult is copied to a textbox bound to the table field or directly to the field in the form's recordset and the record saved.
As SOS said we really need to know more about your situation. But it is rarely necessary or wise to save calculated values to your table. In most cases you should merely re-calculate the value as needed.