Question

曲棍球APP。必须查询表2中的所有行并显示玩家NAME而不是播放器ID

*注意：新的堆栈溢出抱歉格式

表1：球员

╔═════════════════════╗
║ id | fname | lname  ║
╠═════════════════════╣
║ 1 | Jason | McFee   ║
║ 2 | John | Smith    ║
║ 3 | Jack | Doe      ║
╚═════════════════════╝

表2：events_goals

╔═════════════════════════╗
║ id  g_id  a1_id  a2_id  ║
╠═════════════════════════╣
║ 1   1  2  3             ║
║ 2   3  1  2             ║
║ 3   2  1  3             ║
╚═════════════════════════╝

我想要做的是从events_goals获取每一行并使用匹配的玩家名称返回

我想要成就什么：玩家名字被执行了，我不需要名字旁边的（＃）我只是把它放在那里引用玩家ID

表3

╔════════════════════════════════════════════════╗
║ id  goal  assist1  assist2                     ║
╠════════════════════════════════════════════════╣
║ 1  Jason McFee(1)  John SMith(2)  Jack Doe(3)  ║
║ 2  Jack Doe(3)  Jason McFee(1)  John Smith(2)  ║
║ 3  John Smith(2)  Jason McFee(1)  Jack Doe (3) ║
╚════════════════════════════════════════════════╝

我做了什么

我尝试了很多不同的查询，这是迄今为止最好的查询

SELECT players.fname AS GFN, 
       players.lname AS GLN 
FROM   events_goals 
       LEFT JOIN players 
              ON events_goals.g_id = players.playerid

返回：

╔═══════════════╗
║ GFN  GLN      ║
╠═══════════════╣
║ Jason  McFee  ║
║ Jack  Doe     ║
║ John  Smith   ║
╚═══════════════╝

我可以为Assists1和Assists 2运行相同的代码，但是我无法成功地将所有3个SELECT查询加入到一起，理想情况下我想将第一个和最后一个名称列加入到1个单元格中，但我可以不用它，主要是将所有ID转换为名称

Answer 1

JOIN表players在表event_goals上三次，因为有三列依赖于players.id。

SELECT  a.ID,
        CONCAT_WS(' ', b.fname, b.lname) goal,
        CONCAT_WS(' ', c.fname, c.lname) assist1,
        CONCAT_WS(' ', d.fname, d.lname) assist2
FROM    event_goals a
        INNER JOIN players b
            ON a.g_id = b.id
        INNER JOIN players c
            ON a.a1_id = c.id
        INNER JOIN players d
            ON a.a2_id = d.id
ORDER   BY a.id

SQLFiddle Demo

SQL将三个SELECT JOINS合并到一个表中

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