CakePHP database configuration details are in a file that is located at app/Config/database.php.
This database file user can edit the file in the notepad or sublime and can edit the feilds by which it will be connected to the database.Filling all fields to it like hostname, password and database name.It should be change according to your database in which user doing work.

Source Code

class DATABASE_CONFIG {

	public $default = array(
		'datasource' => 'Database/Mysql',
		'persistent' => false,
		'host' => 'localhost',
		'login' => 'root',
		'password' => '',
		'database' => 'cakephp',
		'prefix' => '',
		//'encoding' => 'utf8',
	);

	public $test = array(
		'datasource' => 'Database/Mysql',
		'persistent' => false,
		'host' => 'localhost',
		'login' => 'user',
		'password' => 'password',
		'database' => 'test_database_name',
		'prefix' => '',
		//'encoding' => 'utf8',
	);
}