Be sure to create and keep backup copies of your data. To ensure the consistency of your data and your outlines, you should backup the multidimensional application directory, key DB2 OLAP Server files and any DB2 databases that contain OLAP data at the same time. Before you back up your data, verify that the data is valid by running the VALIDATE command to validate each cube in your application. The VALIDATE command ensures that cubes are valid by checking that the fact tables are consistent with the key tables. If a cube is invalid, you must restore your data from a backup copy. A good time to back up data is after you have made changes to your application, such as loading new data and running calculations. After you back up your data, you must also back up your database using your normal relational database methods. See your relational database documentation for information on backing up a relational database.