我正在制作一个程序，为4名玩家的任何视频游戏排队玩家
这是我的表结构：
CREATE TABLE IF NOT EXISTS `ozbah_users` (
`user_id` int(11) NOT NULL AUTO_INCREMENT,
`user_name` varchar(255) NOT NULL,
`user_status` varchar(2) NOT NULL,
`user_priority` varchar(2) NOT NULL,
`user_event_id` int(11) NOT NULL,
`user_modifiedon` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
PRIMARY KEY (`user_id`),
KEY `user_event_id` (`user_event_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=10 ;
+-----------------+--------------+------+-----+-------------------+-------------
---+
| Field | Type | Null | Key | Default | Extra
|
+-----------------+--------------+------+-----+-------------------+-------------
---+
| user_id | int(11) | NO | PRI | NULL | auto_increme
nt |
| user_name | varchar(255) | NO | | NULL |
|
| user_priority | varchar(2) | NO | | NULL |
|
| user_status | varchar(2) | NO | | NULL |
|
| user_event_id | int(11) | NO | MUL | NULL |
|
| user_modifiedon | timestamp | NO | | CURRENT_TIMESTAMP |
|
+-----------------+--------------+------+-----+-------------------+-------------
这是插入的数据：
INSERT INTO `ozbah_users` (`user_id`, `user_name`, `user_priority`, `user_status`, `user_event_id`, `user_modifiedon`) VALUES
(1, 'A', 'A1', 'A', 1, '2015-06-26 19:22:45'),
(2, 'B', 'A2', 'A', 1, '2015-06-26 20:02:25'),
(3, 'C', 'A3', 'A', 1, '2015-06-26 20:22:16'),
(4, 'D', 'A4', 'A', 1, '2015-06-26 20:22:17'),
(5, 'E', 'W1', 'A', 1, '2015-06-26 20:22:19'),
(6, 'F', 'W2', 'A', 1, '2015-06-26 20:22:35'),
(7, 'G', 'W3', 'A', 1, '2015-06-26 20:22:55');
(8, 'H', 'W4', 'A', 1, '2015-06-26 20:32:15'),
mysql> SELECT * FROM `ozbah_users`
-> ORDER BY `ozbah_users`.`user_modifiedon` ASC;
+---------+-----------+---------------+-------------+---------------+-----------
----------+
| user_id | user_name | user_priority | user_status | user_event_id | user_modif
iedon |
+---------+-----------+---------------+-------------+---------------+-----------
----------+
| 1 | A | A1 | A | 1 | 2015-06-26
22:22:45 |
| 2 | B | A2 | A | 1 | 2015-06-26
23:02:25 |
| 3 | C | A3 | A | 1 | 2015-06-26
23:22:16 |
| 4 | D | A4 | A | 1 | 2015-06-26
23:22:17 |
| 5 | E | W1 | A | 1 | 2015-06-26
23:22:19 |
| 6 | F | W2 | A | 1 | 2015-06-26
23:22:35 |
| 7 | G | W3 | A | 1 | 2015-06-26
23:22:55 |
| 6 | H | W4 | A | 1 | 2015-06-26
23:22:35 |
| 7 | I | W5 | A | 1 | 2015-06-26
如您所见，user_priority为活跃或当前玩家An提供2个值Wn等待玩家 n 是玩家列表的队列数
活跃玩家An从1到4
等待玩家Wn从1到无限制
条件是活跃玩家是2支队伍
第1组：user_priority A1和A2
第2组：user_priority A3和A4
如果球队输掉比赛，两名球员都将移至等候名单的末尾， 并且等待名单中的第一名队员将移动到活动列表的末尾，并且获胜队将在活动玩家列表中移动到顶部
例如，团队2失败，因此A3和A4将移至等待列表的末尾，等待列表的前2个名称将结束活动列表 我只会更改玩家的名字和user_modifiedon
这里的主要问题是我想更新（Active的2行或4行） 球员）和（等待名单中的所有东西都将被转移）这就是什么 我需要！
因为在这种情况下我需要为每一行创建一个更新语句
+---------+-----------+---------------+-------------+---------------+-----------
----------+
| user_id | user_name | user_priority | user_status | user_event_id | user_modif
iedon |
+---------+-----------+---------------+-------------+---------------+-----------
----------+
| 1 | A | A1 | A | 1 | 2015-06-26
22:22:45 |
| 2 | B | A2 | A | 1 | 2015-06-26
23:02:25 |
| 3 | E | A3 | A | 1 | 2015-06-26
23:22:16 |
| 4 | F | A4 | A | 1 | 2015-06-26
23:22:17 |
| 5 | G | W1 | A | 1 | 2015-06-26
23:22:19 |
| 6 | H | W2 | A | 1 | 2015-06-26
23:22:35 |
| 7 | I | W3 | A | 1 | 2015-06-26
23:22:55 |
| 8 | C | W4 | A | 1 | 2015-06-26
23:42:18 |
| 9 | D | W5 | A | 1 | 2015-07-01
22:32:49 |
+---------+-----------+---------------+-------------+---------------+-----------
----------+
我在java中使用2个arraylists创建类似的东西，比如这是java代码
这2个arraylist将包含 Active 和等待玩家
的列表 public class ArrayListDemo {
public static void main(String[] args) {
// create an array list
ArrayList current = new ArrayList();
ArrayList waiting = new ArrayList();
// Display size
System.out.println("Initial size of current: " + current.size());
System.out.println("Initial size of waiting: " + waiting.size());
// add elements to the current array list
current.add("A");
current.add("B");
current.add("C");
current.add("D");
System.out.println("Size of current after additions: " + current.size());
// add elements to the waiting array list
waiting.add("E");
waiting.add("F");
System.out.println("Size of waiting after additions: " + waiting.size());
// display the array list
System.out.println("Contents of current: " + current);
System.out.println("Contents of waiting: " + waiting);
// Remove elements from current array list
current.add(waiting.get(0));
current.add(waiting.get(1));
System.out.println("Contents of current BEFORE Deleting: " + current);
System.out.println("Size of current BEFORE Deleting: " + current.size());
waiting.add(current.get(0));
waiting.add(current.get(1));
System.out.println("Contents of waiting BEFORE Deleting: " + waiting);
System.out.println("Size of waiting BEFORE Deleting: " + waiting.size());
current.remove(0);
System.out.println("current.get(0): "+current.get(0));
current.remove(0);
System.out.println("current.get(0): "+current.get(0));
System.out.println("Contents of current AFTER Deleting: " + current);
waiting.remove(0);
waiting.remove(0);
System.out.println("Contents of waiting AFTER Deleting: " + waiting);
}
}
这是输出
Initial size of current: 0
Initial size of waiting: 0
Size of current after additions: 4
Size of waiting after additions: 2
Contents of current: [A, B, C, D]
Contents of waiting: [E, F]
Contents of current BEFORE Deleting: [A, B, C, D, E, F]
Size of current BEFORE Deleting: 6
Contents of waiting BEFORE Deleting: [E, F, A, B]
Size of waiting BEFORE Deleting: 4
current.get(0): B
current.get(0): C
Contents of current AFTER Deleting: [C, D, E, F]
Contents of waiting AFTER Deleting: [A, B]
我的问题是，更新多行并保持序列正确的最佳SQL查询是什么？
这里的主要问题是我想更新（Active的2行或4行） 球员）和（等待名单中的所有东西都将被转移）这就是什么 我需要！
谢谢
答案 0 :(得分：1)
如果您要删除W2并需要将所有较高级别的内容删除，则可以执行以下操作：
SET @delete = 2;
UPDATE ozbah_users
SET user_priority =
CASE
WHEN user_priority LIKE 'W%' AND user_priority < CONCAT('W', @delete)
THEN CONCAT('A', SUBSTR(user_priority, 2) + 2
WHEN user_priority = CONCAT('W', @delete)
THEN -1
WHEN user_priority LIKE 'W%' AND user_priority > CONCAT('W', @delete)
THEN CONCAT('W', SUBSTR(user_priority, 2) - 2)
END
WHERE user_priority LIKE 'W%'