high-performance database - server dependency package

 OpenLink Virtuoso is a high-performance object-relational SQL database.
 It provides transactions, a smart SQL compiler, hot backup, SQL:1999
 support, a powerful stored-procedure language supporting server-side
 Java or .NET, and more. It supports all major data-access interfaces,
 including ODBC, JDBC, ADO.NET, and OLE/DB.
 .
 This is an empty package depending on the current "best" version of the
 Virtuoso server framework, as recommended by the maintainers (currently
 virtuoso-opensource-6.1). Install this package if in doubt about
 which version you need.