Question

我有一个称为游戏的表（game_id，home_id，home_score，away_id，away_score，date）和一个名为team（team_id，team_name）的表。我需要一个SQL查询来基于home_score和away_score计算每个团队的总得失和获胜百分比（胜出/比赛数）记录。

select game_id, home_score, away_score, case when home_score > away_score then 'true' else 'false ' end from game_schedule

尝试过此操作，但无法执行我想要的操作。谢谢！

Answer 1

取消数据透视并聚合：

select team_id, sum(is_win) as num_wins, sum(is_loss) as num_losses,
       avg(is_win) as win_ratio
from ((select home_id as team_id,
              (case when home_score > away_score then 1 else 0 end) as is_win,
              (case when home_score < away_score then 1 else 0 end) as is_loss
       from games
      ) union all
      (select away_id,
              (case when away_score > home_score then 1 else 0 end) as is_win,
              (case when away_score < home_score then 1 else 0 end) as is_loss
       from games
      )
     ) g
group by team_id;

Answer 2

加入表并使用条件聚合：

select tt.team_id, tt.team_name,
  sum(case when result > 0 then 1 else 0 end) totalwin,
  sum(case when result < 0 then 1 else 0 end) totalloss,
  100.0 * avg(case when result > 0 then 1 else 0 end) percentwin 
from (
  select t.team_id, t.team_name,
    (g.home_score - g.away_score) * case 
      when t.team_id = g.home_id then 1
      when t.team_id = g.away_id then -1
    end result 
  from team t left join games g
  on t.team_id in (g.home_id, g.away_id)
) tt
group by tt.team_id, tt.team_name

查看简化的demo。

如何基于此SQL表计算总的赢利和亏损

2 个答案: