1366 - Incorrect integer value: '' for column `argus_xtc`.`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', '4tc1l81v1p91b5odq0uggmtv86', '18.215.161.19', '1560711762', '1560711762', '/shop/product_info.php?info=p8_Kamera-im-Rauchmelder-mit-SONY-CCD-480TVL-1-0Lux.html')

[XT SQL Error]