This MySQL table had me perplexed for a moment:

mysql> desc quux;
+---------------------------+-----------------------+------+-----+---------+----------------+
| Field                     | Type                  | Null | Key | Default | Extra          |
+---------------------------+-----------------------+------+-----+---------+----------------+
| foobar                    | int(11)               | NO   |     | NULL    |                |
(...)

mysql> show create table quux;
(...)
`foobar` int(11) NOT NULL,
(...)

Since the foobar field was never created with a DEFAULT clause, it gets automatically assigned DEFAULT NULL. However, at a first sight this looks like contradicting the fact that it was also defined as NOT NULL.

Then I realized that this schema aims to force to insert a value (and a non-NULL one) in foobar when adding a new record.

Is this an acceptable way to do so, or there are better ways?