There are no events tied to fields in a table, and the simple truth is data entry should never be done directly into a table but rather thru a form. The incidence of corruption rises sharply when data is entered directly in a table.
You can either make a form based on your table, with the Form Wizard, if necessarty, or, and this is preferable, make a query based on your table, including all the fields, then base your form on the query.
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