mysql 特定查询

Question

我有两个表:teams和 formations :

表团队:

team_id | team_name
   1    | Barcelona
   2    | Real Madrid
   3    | PSG

表格构成:

formation_id | team_id | module
    1        |    2    | 5-3-2
    2        |    1    | 4-4-2
    3        |    3    | 4-4-2
    4        |    2    | 4-4-3

实际上，我需要在 2 个表 GROUP BY team_id 之间进行“连接”，但需要使用最后一个“formation_id”

结果是这样的:

 team_id | team_name  | formation_id  | module
    1    | Barcelona  |     2         |  4-4-2
    2    | Real Madrid|     4         |  4-4-3
    3    | PSG        |     3         |  4-4-2 

实际上我的查询是:

SELECT *
  FROM formations f
 INNER JOIN teams t 
    ON (f.team_id = t.team_id)
 GROUP BY t.team_id

通过查询，我为每个团队选择了第一个插入阵型，而我必须为每个团队选择最后一个阵型。

Answer 1

检查这个 SQLFIDDLE

SELECT A.team_id,A.team_name,B.formation_id,B.module
FROM teams A,formations B
WHERE A.team_id=B.team_id
AND B.formation_id =
(
  SELECT max(formation_id)
  FROM formations C
  WHERE C.team_id =B.team_id
 )
ORDER BY A.team_id;


create table teams
(  
  team_id int
 ,team_name varchar(40)
);
create table formations 
(
  formation_id int
 ,team_id  int
 ,module int
);
insert into teams
values
(1,'Barcelona'),(2,'Real Madrid'),(3,'PSG');
insert into formations
values
(1,2,532),(2,1,442),(3,3,442),(4,2,443);