我想知道从排行榜玩家的位置(排名)。我并没有排行榜表,它正在从users
表和查询生成。这是我得到的条目:
SELECT
u.id as userId,
u.xp as xp,
u.nickname as nickname,
SUM(opr.games_won) as wonGames,
SUM(opr.games_lost) as lostGames
FROM
users u
INNER JOIN
opponent_player_result opr ON u.id = opr.user_id
WHERE
u.last_login >= 1548374400000
AND u.xp > 0
AND u.zone_id = 1
GROUP BY
u.id
ORDER BY
u.xp DESC,
wonGames DESC,
lostGames ASC
LIMIT 0, 50;
该xp
栏是用于存储玩家的经验值。每场比赛后,在更新播放此列。
该opponent_player_result
是分隔的表,我保持玩家的玩的游戏的结果:
+----+------------+-----------+-----------------+---------+
| id | games_lost | games_won | opponent_player | user_id |
+----+------------+-----------+-----------------+---------+
| 1 | 3 | 0 | 0 | 1 |
| 2 | 2 | 1 | 1 | 1 |
| 3 | 0 | 3 | 2 | 1 |
| 4 | 4 | 2 | 0 | 2 |
| 5 | 0 | 1 | 1 | 2 |
| 6 | 1 | 1 | 2 | 2 |
| 7 | 2 | 3 | 0 | 3 |
| 8 | 3 | 0 | 1 | 3 |
| 9 | 3 | 4 | 2 | 3 |
+----+------------+-----------+-----------------+---------+
正如你可能已经注意到,每个玩家都具有3个对手选手的结果(因为只有3个机器人,玩家可以玩)。
上面的查询会给我以下结果:
+--------+----+----------+----------+-----------+
| userId | xp | nickname | wonGames | lostGames |
+--------+----+----------+----------+-----------+
| 1 | 34 | nick1 | 4 | 5 |
| 3 | 29 | nick3 | 7 | 8 |
| 2 | 29 | nick2 | 4 | 5 |
+--------+----+----------+----------+-----------+
我不使用MySQL RANK()
功能,无论我不递增变量玩家位置关联(也许这是我应该做的)。
如何从上面的排行榜结果的单一玩家的位置?
例如,#id 3
用户将有秩2
。
这是我的工作,以找到在排行榜中的玩家的位置查询:
SELECT u.id AS userId,
u.xp AS xp,
1 +
(SELECT COUNT(*)
FROM
(SELECT SUM(opr.games_won) AS wonGames,
SUM(opr.games_lost) AS lostGames
FROM users AS p
INNER JOIN opponent_player_result AS opr ON p.id = opr.user_id
WHERE p.last_login >= 1548374400000
AND p.xp > 0
AND p.xp > u.xp
AND p.zone_id = 1
GROUP BY p.id
ORDER BY p.xp DESC, wonGames DESC, lostGames ASC) AS counter) AS ranking
FROM users AS u
WHERE u.id = 1;
但我发现了以下错误:
ERROR 1054(42S22):未知列 'u.xp' 在 'where子句'
据我所知,MySQL允许只有1级深嵌套子查询或,但在我的例子,我3级深。但是,如何从子查询,然后参照外部查询?
这是获得领先的正确方法?我应该创建一个分离的表,并定期更新呢?我很害怕性能损失。
我使用MySQL 8.0版本。
这是简单的使用MySQL 8.0的排名函数。例如,DENSE_RANK
计算一个分区中的每一行的排名(并列记录被分配了相同级别)。
SELECT
u.id as userId,
u.xp as xp,
u.nickname as nickname,
SUM(opr.games_won) as wonGames,
SUM(opr.games_lost) as lostGames,
DENSE_RANK() OVER(ORDER BY u.xp DESC) rnk
FROM
users u
INNER JOIN
opponent_player_result opr ON u.id = opr.user_id
WHERE
u.last_login >= 1548374400000
AND u.xp > 0
AND u.zone_id = 1
GROUP BY
u.id, u.xp, u.nickname
ORDER BY
u.xp DESC,
wonGames DESC,
lostGames ASC
LIMIT 0, 50;
| userId | xp | nickname | wonGames | lostGames | rnk |
| ------ | --- | -------- | -------- | --------- | --- |
| 1 | 34 | nick1 | 4 | 5 | 1 |
| 3 | 29 | nick3 | 7 | 8 | 2 |
| 2 | 29 | nick2 | 4 | 5 | 2 |