1366 - Incorrect integer value: '' for column `usr_web74_1`.`whos_online`.`customer_id` at row 1

insert into whos_online (customer_id, full_name, session_id, ip_address, time_entry, time_last_click, last_page_url) values ('', 'Guest', 't49rea9esotopvqjk9eotap7t7', '216.73.216.80', '1760388446', '1760388446', '/index.php?cat=c39_Taschen.html')

[XT SQL Error]