Connection.from_string
Description:
[ Version ( since = "5.0.2" ) ]
public Connection.from_string (string? provider_name, string cnc_string, string? auth_string, ConnectionOptions options) throws Error
Opens a connection given a provider ID and a connection string.
This allows applications to open connections without having to create a data source (DSN) in the configuration. The format of cnc_string
is similar to PostgreSQL and MySQL connection strings. It is a semicolumn-separated series of <key>=<value>
pairs, where each key and value are encoded as per RFC 1738, see rfc1738_encode
for more information.
The possible keys depend on the provider, the "gda-sql-6.0 -L" command can be used to list the actual keys for each installed database provider.
For example the connection string to open an SQLite connection to a database file named "my_data.db" in the current directory would be < constant>"DB_DIR=.;DB_NAME=my_data"</constant>.
The cnc_string
string must have the following format: "[<provider>://][<username>[:<password
>]@]<connection_params>" (if <username> and/or <password> are provided, and auth_string
is null, then these username and passwords will be used, and if <provider> is provided
and provider_name
is null then this provider will be used). Note that if provided, &
lt;username>, <password> and <provider> must be encoded as per RFC 1738, see
rfc1738_encode for more information.
The auth_string
must contain the authentication information for the server to accept the connection. It is a string containing
semi-colon seperated named values, usually like "USERNAME=...;PASSWORD=..." where the ... are replaced by actual values. Note that each name and
value must be encoded as per RFC 1738, see rfc1738_encode for more
information.
The actual named parameters required depend on the provider being used, and that list is available as the <parameter>auth_params< /parameter> member of the ProviderInfo structure for each installed provider ( use get_provider_info to get it). Similarly to the format of the connection string, use the "gda-sql-6.0 -L" command to list the possible named parameters.
Additionally, it is possible to have the connection string respect the "<provider_name>://<real cnc string>"
format, in which case the provider name and the real connection string will be extracted from that string (note that if provider_name
is not null then it will still be used as the provider ID).\
This method may fail with a GDA_CONNECTION_ERROR domain error (see the ConnectionError error codes) or a gda_config_error domain error (see the ConfigError error codes).
The returned connection is not yet opened, you need to call open or open_async.
Parameters:
provider_name |
provider ID to connect to, or null |
cnc_string |
connection string. |
auth_string |
authentication string, or null |
options |
options for the connection (see ConnectionOptions). |
Returns:
a new Connection or null if there was an error. |