Use the DEFAULT keyword:
$query = "INSERT INTO myTable VALUES (DEFAULT,'Fname', 'Lname', 'Website')";
Also, you can specify the columns, (which is better practice):
$query = "INSERT INTO myTable
(fname, lname, website)
VALUES
('fname', 'lname', 'website')";
Reference:
- http://dev.mysql.com/doc/refman/5.6/en/data-type-defaults.html