Question

问题：显示具有以下条件的所有玩家的姓名：最小和最大游戏数之间的差异这个玩家大于5。

select p.name
from player p
join competition c
on c.playerID = p.playerID
where (
(select count(*) from competition
 where count(games) > 1
 group by playerID
) - (
select count(*) from competition
  where count(games) <= 1
  group by playerID
))> 5;

我有点迷茫。我不确定这是正确的方法，该如何进行：我应该使用 count 并找到最小和最大游戏数并与大于5进行比较，还是应该使用< strong> count ，最小和最大功能。如果有人可以向我解释这个逻辑，将不胜感激。

表格：

player       competition
-------      --------
playerID     playerID
name         games
birthday     date
address      
telefon

Answer 1

SELECT 
P.Name,
MIN(C.Games) MinGame,
MAX(C.Games) MaxGame,
FROM Player P
INNER JOIN Competition C
ON C.PlayerId = P.PlayerId
GROUP BY P.Id, P.Name
HAVING MAX(C.Games) -  MIN(C.Games)  > 5

Answer 2

这应该是一个简单的查询：

With tab1 AS (Select player.name, min(games) mx_game, max(games) min_game,
max(games) - min(games) diff
from player JOIN competition ON player.player_id = competition.id
group by player.player_id, player.name)

Select tab1.name from tab1
WHERE diff >5;

我要在组中添加player_id，因为player_name可能与2个人相似。

最小和最大游戏数之间的差异

2 个答案: