Open config/settings.inc.php
define('_DB_SERVER_', 'localhost');
define('_DB_NAME_', 'mysite');
define('_DB_USER_', 'root');
define('_DB_PASSWD_', '');
define('_DB_PREFIX_', 'tt_');
Open database with PHPmyadmin and open prefix_shop_url table.
For domain => localhost, domain_ssl=localhost, physical_uri => /presta/