mssql_select_db() sets the current active
database on the server that's associated with the specified link
identifier.
Every subsequent call to mssql_query() will be
made on the active database.
Parameters
database_name
The database name.
To escape the name of a database that contains spaces, hyphens ("-"),
or any other exceptional characters, the database name must be
enclosed in brackets, as is shown in the example, below. This
technique must also be applied when selecting a database name that is
also a reserved word (such as primary).
If no link identifier is specified, the last opened link is assumed.
If no link is open, the function will try to establish a link as if
mssql_connect() was called, and use it.