Where you can use validation rules
Microsoft Access
You can define validation rules for table fields and for controls on forms. When you define rules for tables, those rules apply when you import data. To add validation rules to a table, you open the table and use commands on the Fields tab of the ribbon. To add validation rules to a form, you open the form in Layout view and add rules to the properties of individual controls.
The steps in the section Add a validation rule to a table explain how to add validation rules to table fields. The steps in the section Add a validation rule to a control on a form, later in this article, explain how to add rules to the properties in individual controls.
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