It is often not sufficient that input data merely exists; it must also have the right format. For example, a date field must have data in a date format. A salary field must have data in a numeric or currency format. There are many ways to ensure the validity of data, including the following methods:

• Use the cfparam tag with the type attribute to validate a variable.
• Use the IsValid function to validate a variable.
• Use the cfqueryparam tag in a SQL WHERE clause to validate query parameters.
• Use cfform controls that have validation attributes.
• Use a form input tag with a hidden attribute to validate the contents of a form input field.

For detailed information on validating data in forms and variables, see Validating Data For detailed information on validating query parameters, see Using cfqueryparam.