Question

我正在计算玩家等级的MIN，MAX和AVG：

SELECT
     MIN(`p`.`level`) AS 'min',
     MAX(`p`.`level`) AS 'max',
     AVG(`p`.`level`) AS 'avg'
FROM `dfh`.`players` `p`

如何获取引用p.name和MIN的{{1}}字段值？

的Fe。我在MAX表中得到了这个值：

查询将撤消以下内容：

Lp. | Name | Level
1   | Test | 12
2   | Tesx | 15
3   | Anot | 150

但我希望它还撤销与MIN: 12 MAX: 150和Name值相对应的MIN：

MAX

我该怎么做？

Answer 1

尝试此查询 -

SELECT 'MIN' property, GROUP_CONCAT(p1.name) name, p1.level FROM players p1
  JOIN (SELECT MIN(level) level FROM players) p2
    ON p1.level = p2.level
UNION
SELECT 'MAX' property, GROUP_CONCAT(p1.name) name, p1.level FROM players p1
  JOIN (SELECT MAX(level) level FROM players) p2
    ON p1.level = p2.level

使用最高'经验'值和任何'id'进行查询 -

SELECT * FROM

  (SELECT 'MIN' property, p1.id, p1.level, p1.name FROM players p1
    JOIN (
      SELECT
        level, MAX(experience) experience
      FROM
        players,
        (SELECT @level:=MIN(level) FROM players) t
      WHERE level = @level
    ) p2
    ON p1.experience = p2.experience AND p1.level = p2.level
  ORDER BY id LIMIT 1) t_min

UNION

SELECT * FROM 

  (SELECT 'MAX' property, p1.id, p1.level, p1.name FROM players p1
    JOIN (
      SELECT
        level, MAX(experience) experience
      FROM
        players,
        (SELECT @level:=MAX(level) FROM players) t
      WHERE level = @level
    ) p2
    ON p1.experience = p2.experience AND p1.level = p2.level
  ORDER BY id LIMIT 1) t_max

将此数据集用作子查询以与另一个表连接 -

SELECT * FROM 
(
  SELECT * FROM

    (SELECT 'MIN' property, p1.id, p1.level, p1.name FROM players p1
      JOIN (
        SELECT
          level, MAX(experience) experience
        FROM
          players,
          (SELECT @level:=MIN(level) FROM players) t
        WHERE level = @level
      ) p2
      ON p1.experience = p2.experience AND p1.level = p2.level
    ORDER BY id LIMIT 1) t_min

  UNION

  SELECT * FROM 

    (SELECT 'MAX' property, p1.id, p1.level, p1.name FROM players p1
      JOIN (
        SELECT
          level, MAX(experience) experience
        FROM
          players,
          (SELECT @level:=MAX(level) FROM players) t
        WHERE level = @level
      ) p2
      ON p1.experience = p2.experience AND p1.level = p2.level
    ORDER BY id LIMIT 1) t_max
) p
LEFT JOIN guild_member gm
  ON gm.id = p.id

Answer 2

这将有效地返回低/高名称：

select 'MIN', level, name from players order by level limit 1
union all
select 'MAX', level, name from players order by level desc limit 1

注意缺少子查询......

用值计算MySQL

2 个答案: