Joomla PHP code to convert an array of key value pairs

$sql = "SELECT `parameter`, `value` FROM `#__testday_configuration` ";
    $db->setQuery($sql);
    $db->query();
    $results = $db->loadAssocList();
    $config = array();
    foreach($results as $result)
    {
        $config[$result[parameter]] = $result[value];
    }

Now you can use $config['address'] to access the value assigned to address.