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', '8bc76124208b322b60be2a0b34098c86', '54.224.90.25', '1711660490', '1711660490', '/redirect.php?action=product&id=70')

[XT SQL Error]