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', 'mg7qoke7fpq1io0u3er87uo2k0', '3.85.92.139', '1561472108', '1561472108', '/product_info.php/info/p8_TDI-Advanced-Trimix-Manual--deutsch-.html')

[XT SQL Error]