MonographDAO::getCategories PHP Method

    function getCategories($monographId, $pressId = null)
    {
        $params = array((int) $monographId);
        if ($pressId) {
            $params[] = (int) $pressId;
        }
        $categoryDao = DAORegistry::getDAO('CategoryDAO');
        $result = $this->retrieve('SELECT	c.*
			FROM	categories c,
				submission_categories sc,
				submissions s
			WHERE	c.category_id = sc.category_id AND
				s.submission_id = ? AND
			' . ($pressId ? ' c.press_id = s.context_id AND s.context_id = ? AND' : '') . '
				s.submission_id = sc.submission_id', $params);
        // Delegate category creation to the category DAO.
        return new DAOResultFactory($result, $categoryDao, '_fromRow');
    }