Question

我的表：

players (id_player, id_team)
playerLogros (id_logro, id_player, TD, id_match)道明是玩家得分的次数
matchs (id_match, status)状态说明游戏是否已完成
team_match (id_team, id_match, tipo) tipo：Local / Visitante

我需要知道一支球队赢了多少场比赛。这取决于两队在一场比赛中得分的TD。

我无法改变数据库的结构。我可以得到一支球队得分的TD，但与此同时，我不知道如何让其他球队得分。

我当前的查询：

SELECT SUM(playerLogros.TD)
FROM playerLogros
LEFT JOIN players ON players.id_player=playerLogros.id_player
LEFT JOIN team_match ON team_match.id_team=players.id_team
LEFT JOIN matchs ON matchs.id_match = team_match.id_match
WHERE matchs.status='ended'
GROUP BY...

这里有一些样本：

INSERT INTO players (id_player, id_team) VALUES 
(1,1), (2,1), (3,1), (4,1), 
(5,1), (6,1), (7,1), (8,1), 
(9,1), (10,1), (11,1), (12,2), 
(13,2), (14,2), (15,2), (16,2), 
(17,2), (18,2), (19,2), (20,2), 
(21,2), (22,2), (23,4), (24,4), 
(25,4), (26,4), (27,4), (28,4), 
(29,4), (30,4), (31,4), (32,4), 
(33,4), (34,5), (35,5), (36,5), 
(37,5), (38,5), (39,5), (40,5), 
(41,5), (42,5), (43,5), (44,5);

INSERT INTO  playerLogros (id_logro, id_player, TD, id_match) VALUES
(1,2,1,1), (2,10,1,1), (3,15,1,1), (4,29,2,2), (5,38,1,2), 
(6,6,1,3), (7,32,1,3), (8,16,1,4), (9,1,1,5), (10,42,1,5), (11,35,1,5),
(12,25,3,6), (13,28,1,6), (14,15,1,6), (15,29,1,6);

INSERT INTO matchs (id_match, status) VALUES
(1,'ended'),(2,'ended'),(3,'ended'),(4,'ended'),(5,'ended'),(6,'ended');

INSERT INTO team_match (id_team, id_match, tipo) VALUES 
(1,1,'Local'),(2,1,'Visitant'),(4,2,'Local'),(5,2,'Visitant'),
(1,3,'Local'),(4,3,'Visitant'),(2,4,'Local'),(5,4,'Visitant'),
(1,5,'Local'),(5,5,'Visitant'),(4,6,'Local'),(2,6,'Visitant');

查询应该是这样的：

... id_team ... Matches_won ... Matches_tied Matches_lost

... 1 ................ 1 ....................... 1 .. .................... 1

... 2 ................ 1 ....................... 0 .. .................... 2

... 4 ................ 2 ....................... 1 .. .................... 0

... 5 ................ 1 ....................... 0 .. .................... 2

Answer 1

这应该适合你。预查询对每个团队进行聚合（基于玩家关联以对给定匹配进行评分）并按每个团队和匹配组合进行分组。所以最后，你会得到2条比赛记录，每支队伍各有一条记录。

从那里开始，加入回匹配表，找到相应的本地与访客团队ID，并获得相应的值...按匹配分组，以便每次匹配汇总到一行。

SELECT 
      PreSumTDs.id_match,
      MAX( IF( tm.tipo = 'Local', tm.id_team, 0 )) as LocalTeam,
      SUM( IF( tm.tipo = 'Local' and tm.id_team = PreSumTDs.id_team, PreSumTDs.TeamTDs, 0 )) as LocalScore,
      MAX( IF( tm.tipo = 'Visitante', tm.id_team, 0 )) as VisitTeam,
      SUM( IF( tm.tipo = 'Visitante' and tm.id_team = PreSumTDs.id_team, PreSumTDs.TeamTDs, 0 )) as VisitScore
   from 
      ( select 
              pl.id_match,
              p.id_team,
              SUM( pl.TD ) as TeamTDs
           from
              matchs m
                 JOIN playerLogros pl
                    ON m.match_id = pl.match_id
                 JOIN players p
                    ON pl.id_player = p.id_player
           where
              m.status = 'ended'
           group by
              pl.id_match,
              p.id_team ) PreSumTDs
      JOIN team_match tm
         ON PreSumTDs.id_match = tm.id_match
   group by
      tm.id_match

查询涉及多个JOIN的困难

1 个答案: