1366 - Incorrect integer value: '' for column `abtecsho_shop`.`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', 'c9b4qgc37m7uk5o8g4k4osqph1', '216.73.216.85', '1763620061', '1763620061', '/index.php/manufacturers_id/18')

[XT SQL Error]