Mysql 从3个select查询中获取一行结果数据
我有桌子: 玩家:Mysql 从3个select查询中获取一行结果数据,mysql,sql,join,Mysql,Sql,Join,我有桌子: 玩家: id name 地点: id playerId tournamentId 比赛: id name prize1 prize2 prize3 查询: ( select pl.Name, pla.place,sum(t2.prize1),count(t2.name) from players pl inner join places pla on pl.id = pla.PlayerId inner join tournaments2 t
id
name
地点:
id
playerId
tournamentId
比赛:
id
name
prize1
prize2
prize3
查询:
(
select pl.Name, pla.place,sum(t2.prize1),count(t2.name)
from players pl
inner join places pla on pl.id = pla.PlayerId
inner join tournaments2 t2 on pla.tournamentId = t2.id
where pla.place = 1
group by pl.name
) union (
select pl.Name, pla.place,sum(t2.prize2),count(t2.name)
from players pl
inner join places pla on pl.id = pla.PlayerId
inner join tournaments2 t2 on pla.tournamentId = t2.id
where pla.place = 2 group by pl.name
) union (
select pl.Name, pla.place,sum(t2.prize3),count(t2.name)
from players pl
inner join places pla on pl.id = pla.PlayerId
inner join tournaments2 t2 on pla.tournamentId = t2.id
where pla.place = 3 group by pl.name
)
结果:
Name place gold placecount
"player1" "1" "1500" "2"
"player2" "1" "500" "1"
"player1" "2" "300" "1"
"player1" "3" "200" "1"
所需数据表示:
name gold1stplace 1stplacecount gold2ndplace 2ndplacecount gold3rdplace 3rdplacecount
"player1" "1500" "3" "300" "1" "200" "1"
如何实现所需的数据表示?应该可以使用条件聚合来解决此问题:
应该可以使用条件聚合来解决此问题:
问题是什么?我不明白如何从我现在拥有的东西中实现所需的数据表示。问题是什么?我不明白如何从我现在拥有的东西中实现所需的数据表示
SELECT
p.name player,
SUM(CASE WHEN pc.place = 1 THEN t.prize1 ELSE 0 END) gold1stplace,
SUM(CASE WHEN pc.place = 1 THEN 1 ELSE 0 END) place1stcount,
SUM(CASE WHEN pc.place = 2 THEN t.prize2 ELSE 0 END) gold2ndplace,
SUM(CASE WHEN pc.place = 2 THEN 1 ELSE 0 END) place2ndcount,
SUM(CASE WHEN pc.place = 3 THEN t.prize3 ELSE 0 END) gold3rdplace,
SUM(CASE WHEN pc.place = 3 THEN 1 ELSE 0 END) place3rdcount
FROM
players p
INNER JOIN places pc ON pc.playerId = p.id
INNER JOIN tournaments t ON t.id = pc.tournamentId
GROUP BY p.name