Virtual Database (VDB) is a full read-and-write copy of the source data that is provisioned from either a dSource or another VDB. A VDB is provisioned and managed by the Delphix Continuous Data Engine. Upon successfully adding a data source from an environment and generating snapshots of a dSource, you can initiate the provisioning of virtual databases (VDBs).
A dSource is a protected, virtualized representation of a source database which Delphix Continuous Data Engine maintains. It cannot be managed, manipulated, or examined by database tools. It is used to create and update virtual databases. To make use of the dSource snapshots, it is imperative to create a VDB.
It is important to note that the VDBs can also be created from existing VDBs. Once a VDB has been provisioned on the target environment, you have the ability to create a snapshot policy for that VDB. This policy enables you to capture and manage changes within the VDB in the same manner as any other conventional logical or physical database.
Both dSources and VDBs have timeflows, which describes the timeline of data of a virtual database or dSource. Virtual databases can be provisioned from any snapshot in a timeflow. The virtual database's filesystem will be dependent upon the snapshot used to provision, and as such, that snapshot can not be removed until the dependency is removed. In the Delphix Continuous Data Engine UI, a timeflow is represented vertically with a series of individual snapshots as rows.
Snapshots of dSources preserve specific points in time for use later during the virtual database provisioning workflow. Taking a snapshot will create a new snapshot entry in the VDBs timeflow.