Add DSN for non MySQL/MariaDB RDBMSes.

docs/guide/database-basics.md

@@ -19,7 +19,13 @@ return array(
 		// ...
 		'db' => array(
 			'class' => 'yii\db\Connection',
-			'dsn' => 'mysql:host=localhost;dbname=mydatabase',
+			'dsn' => 'mysql:host=localhost;dbname=mydatabase', // MySQL, MariaDB
+			//'dsn' => 'sqlite:/path/to/database/file', // SQLite
+			//'dsn' => 'pgsql:host=localhost;port=5432;dbname=mydatabase', // PostgreSQL
+			//'dsn' => 'sqlsrv:Server=localhost;Database=mydatabase', // MS SQL Server, sqlsrv driver
+			//'dsn' => 'dblib:host=localhost;dbname=mydatabase', // MS SQL Server, dblib driver
+			//'dsn' => 'mssql:host=localhost;dbname=mydatabase', // MS SQL Server, mssql driver
+			//'dsn' => 'oci:dbname=//localhost:1521/testdb', // Oracle
 			'username' => 'root',
 			'password' => '',
 			'charset' => 'utf8',