单个查询中的多个联接

Question

为梦幻足球联赛编写代码。有两张桌子

1. Player_details

   列 - ID,PLAYER_NAME,POINTS

2. USERS

   列 - id,palyer1,player2,player3,........Player11,

用户创建帐户，选择团队中的 11 名球员。球队总分是球员从球员详情表中获得的积分总和。

我想获得每个用户的总数。我举个例子：

USER       player1    player2   player3  Player4 ... ..... ...Player11  Total 

User1        a         b          c        d                      j
user2        d         a          e        b                      k

。 . .

a,b,c.... 是玩家表中的玩家姓名。现在在总列中，我想获得玩家 a、b、c、d、...j 为 User1 得分的总和。

对于用户 2、用户 3、用户 4 也是如此。

任何帮助将不胜感激。

Answer 1

这可能会做你想要的。请注意，由于您的表格结构，您必须为团队中的每个玩家进行连接。正如 cmets 中所述，您应该查看 normalisation。

SELECT u.id AS User,
  p1.PLAYER_NAME AS Player1,
  p2.PLAYER_NAME AS Player2,
  p3.PLAYER_NAME AS Player3,
  p4.PLAYER_NAME AS Player4,
  p5.PLAYER_NAME AS Player5,
  p6.PLAYER_NAME AS Player6,
  p7.PLAYER_NAME AS Player7,
  p8.PLAYER_NAME AS Player8,
  p9.PLAYER_NAME AS Player9,
  p10.PLAYER_NAME AS Player10,
  p11.PLAYER_NAME AS Player11,
  p1.POINTS + p2.POINTS + p3.POINTS + p4.POINTS + p5.POINTS + p6.POINTS + p7.POINTS + p8.POINTS + p9.POINTS + p10.POINTS + p11.POINTS AS Total
FROM USERS u
JOIN Player_details p1 ON p1.ID = u.player1
JOIN Player_details p2 ON p2.ID = u.player2
JOIN Player_details p3 ON p3.ID = u.player3
JOIN Player_details p4 ON p4.ID = u.player4
JOIN Player_details p5 ON p5.ID = u.player5
JOIN Player_details p6 ON p6.ID = u.player6
JOIN Player_details p7 ON p7.ID = u.player7
JOIN Player_details p8 ON p8.ID = u.player8
JOIN Player_details p9 ON p9.ID = u.player9
JOIN Player_details p10 ON p10.ID = u.player10
JOIN Player_details p11 ON p11.ID = u.player11