Database storage

• Local storage is the run time directory directly accessible to the OLAP Service worker by way of the operating system file system. It is usually a folder on a hard drive of the computer running the OLAP Service.
• Central storage is persistent storage, either on Amazon Simple Storage Service (Amazon S3) or any storage available to the operating system file system.

Regardless of the deployment target such as cloud or on premises, an OLAP database is persisted on central storage. When a database is started, the necessary files are downloaded from central storage to local storage.

Functions such as Cube Save and Dimension Save flush the in-memory state of the targeted database to local storage. For being fully persisted, the changes must be transferred back to central storage. That is achieved by saving the database using the Database Save function or by scheduling regular saves using d/EPM Administration.

The database is always saved when it is shutdown.

d/EPM Administration has options that can be used to recover a database if it is corrupted.