>I don't know why the field level validation works so strange.
>I am using BufferingModeOverride = 4, i am not typing anything in the textbox or executing Tableupdate yet.

Juan Carlos,

Field validation rules defined in the database will fire before the valid event of the control or controls that are bound to field in a table. You have a couple of choices to get around this behavior. 1) use local updatable views instead of tables directly, in this case the table's rules will not fire until you do the tableupdate on the view and you can catch things in the valid of the controls and fix them. 2) don't put the validation rules in teh database at all, but rahter enforce them in the controls, this is less desirable as it does not contorl data comming into the tables from sources other than your application.