This function creates a connection and opens it, using a DSN name.
If opening fails, then no connection is created. The named DSN should be available. See Connection.from_dsn_name for more information.
| dsn_name |
data source name. |
| auth_string |
authentication string, or null |
| options |
options for the connection (see ConnectionOptions). |
|
a new Connection if connection opening was successful or null if there was an error. |