( [string servername [, string username [, string password]]] )
Returns: A positive MS SQL persistent link identifier on success,
or FALSE on error.
mssql_pconnect() acts very much like
mssql_connect() with two major differences.
First, when connecting, the function would first try to find a
(persistent) link that's already open with the same host,
username and password. If one is found, an identifier for it
will be returned instead of opening a new connection.
Second, the connection to the SQL server will not be closed when
the execution of the script ends. Instead, the link will remain
open for future use (mssql_close() will not
close links established by mssql_pconnect()).
This type of links is therefore called 'persistent'.