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', 'e9f63fbbc947b1f82dc374c2addb972e', '18.206.160.129', '1711658161', '1711658161', '/index.php')

[XT SQL Error]