mysql - MYSQL IN 子句只返回第一个值组合的结果

Question

我以前使用过这个查询：

SELECT * 
FROM stone_list 
WHERE type IN ('ALEXANDRITE','AMETHYST') 
   AND shape IN ('OVAL') ORDER BY type, shape

过去它对我有用，只是这次它做了一些非常奇怪的事情。当我只有一个 shape 值时IN，查询只返回 type isALEXANDRITE和 shape is 的结果OVAL，即使也有行type = AMETHYST and shape = OVAL。

现在，当我添加第二个形状时，例如shape IN ('OVAL','ROUND')，它将返回两个type = ALEXANDRITE and type = AMETHYST和 for 的值shape = OVAL and shape = ROUND（因此，它按预期工作）。

真的胜过我。

有任何想法的人吗？

谢谢！

Answer 1

查询没有任何问题，因此我只能假设您在问题中忽略或遗漏了某些内容。

mysql> select * from stone_list;
+----+-------------+--------+
| id | type        | shape  |
+----+-------------+--------+
|  1 | ALEXANDRITE | OVAL   |
|  2 | ALEXANDRITE | ROUND  |
|  3 | BASILIC     | OVAL   |
|  4 | AMETHYST    | SQUARE |
|  5 | AMETHYST    | ROUND  |
|  6 | AMETHYST    | OVAL   |
+----+-------------+--------+
6 rows in set (0.00 sec)


mysql> SELECT * FROM stone_list WHERE type IN ('ALEXANDRITE','AMETHYST') AND shape IN ('OVAL') ORDER BY type, shape
    -> ;
+----+-------------+-------+
| id | type        | shape |
+----+-------------+-------+
|  1 | ALEXANDRITE | OVAL  |
|  6 | AMETHYST    | OVAL  |
+----+-------------+-------+
2 rows in set (0.00 sec)


mysql> describe stone_list;
+-------+------------------+------+-----+---------+----------------+
| Field | Type             | Null | Key | Default | Extra          |
+-------+------------------+------+-----+---------+----------------+
| id    | int(10) unsigned | NO   | PRI | NULL    | auto_increment |
| type  | varchar(50)      | YES  |     | NULL    |                |
| shape | varchar(50)      | YES  |     | NULL    |                |
+-------+------------------+------+-----+---------+----------------+
3 rows in set (0.00 sec)