What is Cross Validation Rule?

cross validation is used to prevent the creation of combinations that should never exist

cross validation is used to prevent the creation of combinations that should never exist

cross-validation rules
Rules that restrict the user from entering invalid key flexfield segment value combinations during data entry. For example, you may set up a cross-validation rule that disallows using department segments with balance sheet accounts.

Cross Validation rule checks while attempt to create a new combination of flexfield values. Cross-validation rules have no effect on flexfield combinations that already exist. If you want to disable an existing combination, you must disable that combination specifically using the appropriate window. For example, you can disable an existing Accounting Flexfield combination using the Define Accounting Flexfield Combinations window.