mysql中is null语句的用法分享

2019-01-03 18:27:46王冬梅

    ->                   ('pl/sql',        20,      10,      5,        'classical',  'opera'),
    ->                   ('sql server',    23,      12,      8,        'classical',  'general');
query ok, 16 rows affected (0.00 sec)
records: 16  duplicates: 0  warnings: 0

mysql>
mysql> select * from topic;
+---------+----------------+---------+---------+----------+------------+----------+---------------------+
| topicid | name           | instock | onorder | reserved | department | category | rowupdate           |
+---------+----------------+---------+---------+----------+------------+----------+---------------------+
|       1 | java           |      10 |       5 |        3 | popular    | rock     | 2007-07-23 19:09:45 |
|       2 | javascript     |      10 |       5 |        3 | classical  | opera    | 2007-07-23 19:09:45 |
|       3 | c sharp        |      17 |       4 |        1 | popular    | jazz     | 2007-07-23 19:09:45 |
|       4 | c              |       9 |       4 |        2 | classical  | dance    | 2007-07-23 19:09:45 |
|       5 | c++            |      24 |       2 |        5 | classical  | general  | 2007-07-23 19:09:45 |
|       6 | perl           |      16 |       6 |        8 | classical  | vocal    | 2007-07-23 19:09:45 |
|       7 | python         |       2 |      25 |        6 | popular    | blues    | 2007-07-23 19:09:45 |