MySql为体育联盟的.pct划分

Question

出于某种原因，我不能简单地介绍一些代码。

我想在下面的代码中将“赢”分为“玩”，这样在我的输出中，如果您赢得了4场比赛中的2场比赛，则显示为.500？

确定它很简单，放置可能是关键，但我无法为我的生活摸索它！

$result = mysql_query(" 
    select team, 
    count(*) played, 
    count(case when HomeScore > AwayScore then 1 end) wins, 
    count(case when AwayScore > HomeScore then 1 end) lost, 
    count(case when HomeScore = AwayScore then 1 end) draws, 
    sum(HomeScore) ptsfor, 
    sum(AwayScore) ptsagainst, 
    sum(HomeScore) - sum(AwayScore) goal_diff, 
    sum(case when HomeScore > AwayScore then 3 else 0 end + case 
    when HomeScore = AwayScore then 1 else 0 end) score  
    from (select 
     HomeTeam team, 
     HomeScore, 
     AwayScore 
    from Game 
     union all 
    select AwayTeam, 
     AwayScore, 
     HomeScore 
    from Game) a 
    group by team 
    order by wins desc, 
     draws desc, 
    lost asc, 
    goal_diff desc;"); 

感谢

Answer 1

又一个计算列添加到查询，像这样：因为我假定分数将是整数

select team, 
count(*) played, 
count(case when HomeScore > AwayScore then 1 end) wins, 
(cast(count(case when HomeScore > AwayScore then 1 end) as decimal(8,2)/cast(count(*) as decimal(8,2)) percentage, 
.... -> Rest of the query goes here 

铸造完成。如果没有施法，将会失去准确性，即2/4将在没有施法的情况下返回0。

Answer 2

请尝试以下的查询。这利用了MySQL的行为自动将boolean表达式转换为int。所以这意味着没有CASE语句（漂亮的查询以牺牲可移植性为代价）。此外，SUM(3*win + draw) score等部件在视觉上看起来更像您的分数计算公式。计算没问题pct。

SELECT team 
    , COUNT(*) played 
    , SUM(win) wins 
    , SUM(loss) lost 
    , SUM(win)/count(*) pctWon 
    , SUM(draw) draws 
    , SUM(SelfScore) ptsfor 
    , SUM(OpponentScore) ptsagainst 
    , SUM(SelfScore) - SUM(OpponentScore) goal_diff 
    , SUM(3*win + draw) score 
FROM (
     SELECT team 
    , SelfScore 
    , OpponentScore 
    , SelfScore < OpponentScore win 
    , SelfScore > OpponentScore loss 
    , SelfScore = OpponentScore draw 
     FROM (
     SELECT HomeTeam team, HomeScore SelfScore, AwayScore OpponentScore 
     FROM Game 
     union all select AwayTeam, AwayScore, HomeScore 
     FROM Game 
     ) a 
) b 
GROUP BY team 
ORDER BY wins DESC, draws DESC, lost ASC, goal_diff DESC;