1366 - Incorrect integer value: '' for column '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', 'dabf5266579101759b38af9f61405468', '3.145.12.1', '1713551314', '1713551314', '/product_info.php/info/p1_Rapshonig.html')

[XT SQL Error]