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', 'u4sg8ro2tkdm3nlu6fgt9jb1d7', '18.97.9.170', '1739808305', '1739808305', '/shop_content.php/coID/4/content/Impressum')

[XT SQL Error]