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', '9da99qumuhm7ujdm3kt2f2cld7', '3.233.242.204', '1632155945', '1632155945', '/')

[XT SQL Error]