Applies To: SQL Server 2014, SQL Server 2016 Preview
Returns the database name that is specified by the user in the database connection string. This is the database that is specified by using the sqlcmd -d option (USE database) or the ODBC data source expression (initial catalog =databasename).
This database is not the same as the default user database.
Applies to: SQL Server (SQL Server 2008 through current version).
If the initial database is not specified, the function returns an empty string.