这是MySQL排序错误吗

这是MySQL排序错误吗

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问题描述

我遇到了奇怪的服务器行为MySQL 5.1.50.记录排序不正确.

I was faced with strange server behavior MySQL 5.1.50. It sorts records incorrectly.

例如,我创建了一个表test:

For example I have created a table test:

CREATE TABLE IF NOT EXISTS `test` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `title` varchar(250) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8;


INSERT INTO `test` (`id`, `title`) VALUES
(1, 'record1'),
(2, 'record2'),
(3, 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'),
(4, 'ABCDEFGHIJKLMNOPQRSTUVWXYY');

并进行查询:

mysql>设置名称utf8;查询正常,受影响的0行(0.00秒)

mysql> set names utf8;Query OK, 0 rows affected (0.00 sec)

mysql>从测试顺序中按标题asc选择*;

mysql> select * from test order by title asc;

+----+----------------------------+
| id | title                      |
+----+----------------------------+
|  3 | ABCDEFGHIJKLMNOPQRSTUVWXYZ |
|  4 | ABCDEFGHIJKLMNOPQRSTUVWXYY |
|  1 | record1                    |
|  2 | record2                    |
+----+----------------------------+

组4行(0.00秒)

mysql>从测试顺序中按标题desc选择*;

mysql> select * from test order by title desc;

+----+----------------------------+
| id | title                      |
+----+----------------------------+
|  2 | record2                    |
|  1 | record1                    |
|  3 | ABCDEFGHIJKLMNOPQRSTUVWXYZ |
|  4 | ABCDEFGHIJKLMNOPQRSTUVWXYY |
+----+----------------------------+

组4行(0.00秒)

如您所见,记录3和4不会改变位置

As you see records 3 and 4 don't change places

我进行了这样的查询,并且某些字母不会更改顺序,例如A和a.

I did such query and some letters does not change an order, for example, A and a.

mysql> SELECT * FROM test ORDER BY标题COLLATE utf8_unicode_ci ASC;

mysql> SELECT * FROM test ORDER BY title COLLATE utf8_unicode_ci ASC;

+----+---------+
| id | title   |
+----+---------+
|  1 | A       |
| 27 | a       |
| 28 | b       |
|  2 | B       |
| 29 | c       |
|  3 | C       |
|  4 | D       |
| 30 | d       |
| 31 | e       |
|  5 | E       |
|  6 | F       |
| 32 | f       |
| 33 | g       |
|  7 | G       |
| 34 | h       |
|  8 | H       |
| 35 | i       |
|  9 | I       |
| 36 | j       |
| 10 | J       |
| 11 | K       |
| 37 | k       |
| 12 | L       |
| 38 | l       |
| 39 | m       |
| 13 | M       |
| 40 | n       |
| 14 | N       |
| 41 | o       |
| 15 | O       |
| 42 | p       |
| 16 | P       |
| 17 | Q       |
| 43 | q       |
| 44 | r       |
| 18 | R       |
| 19 | S       |
| 45 | s       |
| 20 | T       |
| 46 | t       |
| 21 | U       |
| 47 | u       |
| 48 | v       |
| 22 | V       |
| 49 | w       |
| 23 | W       |
| 50 | x       |
| 24 | X       |
| 25 | Y       |
| 51 | y       |
| 26 | Z       |
| 52 | z       |
+----+---------+

mysql> SELECT * FROM test ORDER BY标题COLLATE utf8_unicode_ci DESC;

mysql> SELECT * FROM test ORDER BY title COLLATE utf8_unicode_ci DESC;

+----+---------+
| id | title   |
+----+---------+
| 52 | z       |
| 26 | Z       |
| 25 | Y       |
| 51 | y       |
| 50 | x       |
| 24 | X       |
| 49 | w       |
| 23 | W       |
| 48 | v       |
| 22 | V       |
| 47 | u       |
| 21 | U       |
| 20 | T       |
| 46 | t       |
| 45 | s       |
| 19 | S       |
| 18 | R       |
| 44 | r       |
| 17 | Q       |
| 43 | q       |
| 16 | P       |
| 42 | p       |
| 41 | o       |
| 15 | O       |
| 40 | n       |
| 14 | N       |
| 39 | m       |
| 13 | M       |
| 12 | L       |
| 38 | l       |
| 11 | K       |
| 37 | k       |
| 10 | J       |
| 36 | j       |
|  9 | I       |
| 35 | i       |
|  8 | H       |
| 34 | h       |
|  7 | G       |
| 33 | g       |
| 32 | f       |
|  6 | F       |
|  5 | E       |
| 31 | e       |
|  4 | D       |
| 30 | d       |
| 29 | c       |
|  3 | C       |
|  2 | B       |
| 28 | b       |
|  1 | A       |
| 27 | a       |
+----+---------+

我认为这是排序规则的错误.

I think that it is the bug with collation.

也许有人碰到过这种服务器行为吗?

May be someone ran into such conduct of server?

推荐答案

如果尝试怎么办?

SELECT *
FROM test
ORDER BY title ASC
COLLATE utf8_unicode_ci;

您尝试过吗:

INSERT INTO test (id, title)
VALUES
(101, 'A'),
(102, 'B'),
(103, 'C'),
...
(126, 'Z');

SELECT *
FROM test
ORDER BY title ASC
;

要查看问题(或错误)是否与长字符串或排序规则有关?

To see if the problem (or bug) is related to long strings or to collation?

这篇关于这是MySQL排序错误吗?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!

08-24 05:49