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', '6b316adf34f001672bf4f0feb11b79ce', '3.137.221.33', '1722070569', '1722070569', '/advanced_search.php')

[XT SQL Error]