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', '29faqujh5u13nor5n7dlpo9mo4', '107.22.83.0', '1503542692', '1503542692', '/')

[XT SQL Error]