title: sql changing null to 0
body: <p>I am using a web app to get "Quantity On-hand" for an inventory app. The user is actually allowed to leave the box blank when they submit. I set the SQL table field to default to -1. When I go through the insert routine and then look at the database table the value for an item that was not entered is 0. If there was no entry why didn't the default of -1 fill the field and not 0?</p>