Set Default Reference Dialog Box
Use this dialog box to indicate which database will be used when you run scripts or queries within a project. To access this dialog box, right-click the database project node in Solution Explorer, then choose Set Default Reference on the shortcut menu.
The Set Default Reference shortcut command is only available for a database project.
The Set Default Reference dialog box lists the current references for the project and all of the other database connections available in Server Explorer. Each line describes one database reference or one connection. To establish an existing connection or reference as the default, select the appropriate list item and click OK.
When you set the default database reference, several important things happen: the selected default database reference is added to the Database References folder (if not previously added); the icon is changed to designate the default database reference; and the defaults for other commands are changed. For example, if you create a new query, you are automatically prompted to add tables from the default database.