When you create a database with Microsoft Office Access 2003, you can set properties that restrict what can be entered in it.
To ensure the ongoing accuracy of a database, you can create and run action queries that quickly update information or delete selected records from a table.
The Data Type setting restricts entries to a specific type of data: text, numbers, dates, and so on. For example, if the data type is set to Number and you try to enter text, Access refuses your entry and displays a warning.
You can set the Field Size property for the Text, Number, and AutoNumber data types. This property restricts the number of characters allowed in a text field, and the size of numbers that can be entered in a number or AutoNumber field.