Comments - Field 'xxxx' doesn't have a default value

Thanks Ian... But how can I specify a default value for a field that is primary and auto-increment, such as the customer_id field?

Primary key auto-increments can be made null:

ALTER TABLE customer MODIFY customer_id INT(11) NULL AUTO_INCREMENT;

but not given a DEFAULT value, as the AUTO_INCREMENT takes care of that:

ALTER TABLE customer MODIFY customer_id INT(11) NOT NULL DEFAULT '0' AUTO_INCREMENT;
ERROR 1067 (42000): Invalid default value for 'customer_id'

You shouldn't get the "Field 'xxxx' doesn't have a default value" error on an auto-increment, so if you are, it would help to find the queries resulting in the problem as well as the table state at the time of these errors.