Validating data in Microsoft Access allows you to check data whilst it is being entered by the database user and will enable you to not save the data if it breaks any validation rules or routines. It is easy for an end user to make a mistake when they are entering data or even to leave out important details that must be entered, so we need to check this data when it is being entered into the database. Allowing invalid data to be entered into the database ensures that the database and the data available will become less valuable and harder for the user to use.
Microsoft Access provides several methods on how to check the data being entered, and provides the following validation features:
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