CREATE TABLE action (    action_id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,    z_action_id INT UNSIGNED DEFAULT NULL,    z_portal_id INT UNSIGNED DEFAULT NULL,    person_id INT UNSIGNED DEFAULT NULL,    when_done TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,    description TEXT,    ipaddress VARCHAR(15) DEFAULT NULL,    browser VARCHAR(255) DEFAULT NULL,    os VARCHAR(255) DEFAULT NULL,    FOREIGN KEY (z_action_id) REFERENCES z_action(z_action_id) ON UPDATE CASCADE ON DELETE RESTRICT,    FOREIGN KEY (z_portal_id) REFERENCES z_portal(z_portal_id) ON UPDATE CASCADE ON DELETE RESTRICT,    FOREIGN KEY (person_id) REFERENCES person(person_id) ON UPDATE CASCADE ON DELETE RESTRICT ) ENGINE=NDB;