The volumes in which the database content is recorded are called data volumes. Among other things, the data volumes contain the metadata of the database catalog and the application data.
All data volumes together form the data area. The size of the data area represents the total size of the database instance. It must not fall below 2000 pages. In the data area, there must also always be sufficient space to hold all the data that is created during database operations. Make regular backups of the data area.
You can use the Database Manager to display information about the data area.
Database Manager GUI, Displaying Data Area Information
Database Manager CLI, Displaying Information About the Database Instance