To open an existing sample diagram, select File > Open and then double-click on any tab at the bottom of the Sample Data pane. The samples appear in the Sample Data pane on the left side of the screen. Select one or more samples that you want to use as templates and click Open. Select File > New > Existing Sample Data to display the Open dialog box.
The Visio interface provides a large number of sample databases that can be used as templates for creating new diagrams. Database Diagram – Creating a Database Diagram in Visio
Visio provides a vast library of stencils for creating database diagrams. A database diagram shows the relationship between tables, views and other database objects. Visio Database Diagram: Database diagrams are the visual representations of the database objects.
