Question

我正在获取按高尔夫障碍分类的球员记录。像让分盘在0到5之间的玩家位于0-5范围内，同样让分盘在6-11之间的玩家位于6-11范围内，依此类推。我正在尝试从每个范围中获取前3名球员，以便为每个回合设置飞行。

我已经使用partition by子句来分隔记录，并使用ROW_NUMBER从每个范围中获得前3名玩家。为了定义范围，我使用了多种情况。现在，我如何使用range作为别名的分区名称，或者通过哪种方式可以生成正确的结果。以下是我的查询。

  select * from (
  select  uu.Id, firstname, lastname, userhandicap, 
  case when userhandicap>=0 and userhandicap<=5 then '0-5'
  when userhandicap>=6 and userhandicap<=11 then '6-11' 
  when UserHandicap>=12 and UserHandicap<=18 then '12-18' 
  when UserHandicap>=19 and UserHandicap<=26 then '19-26'
  else '27 and above' end as range, RN = ROW_Number()  over (PARTITION BY 
  range order by cast(userhandicap as int))
  from dbo.[User] uu inner join dbo.[EventRegisteredUsers] eru
  on uu.Id = eru.UserId 
  where eru.UserId not in (Select fp.UserId from dbo.[FlightPlayer] fp 
  inner join dbo.[Flight] f
  on fp.FlightId = f.Id 
  where f.Rounds = '1'
  and f.Starthole = '0a9b926e-0baa-4369-8cf8-8fc84ca80d65' and f.EventId = 
  '7de10ad6-098d-419f-9c2d-2e62803ad1f7')
  and eru.EventId = '7de10ad6-098d-419f-9c2d-2e62803ad1f7') uu
  WHERE 
   uu.RN <= 3

Answer 1

您可以使用apply在子查询中的中定义range值。这是定义范围的最简单方法：

select *
from (select uu.Id, firstname, lastname, userhandicap, 
             row_number() over (partition by v.range order by cast(userhandicap as int)) as seqnum
      from dbo.[User] uu inner join
           dbo.[EventRegisteredUsers] eru
           on uu.Id = eru.UserId cross apply
           (values (case when userhandicap <= 5 then '0-5'
                         when userhandicap <= 11 then '6-11' 
                         when UserHandicap <= 18 then '12-18' 
                         when UserHandicap <= 26 then '19-26'
                         else '27 and above'
                    end)
           ) v(range)
      where not exists (select 1
                        from dbo.[FlightPlayer] fp join
                             dbo.[Flight] f
                             on fp.FlightId = f.Id 
                        where eru.UserId = fp.UserId and 
                              f.Rounds = '1' and
                              f.Starthole = '0a9b926e-0baa-4369-8cf8-8fc84ca80d65' and
                              f.EventId = '7de10ad6-098d-419f-9c2d-2e62803ad1f7'
                       ) and
            eru.EventId = '7de10ad6-098d-419f-9c2d-2e62803ad1f7'
       ) uu
where uu.seqnum <= 3;

请注意查询的其他更改：

请勿将not in与子查询一起使用。如果子查询返回一个NULL值，则将所有值过滤掉。（通常）这不是预期的行为。
case表达式过于复杂。使用保证case来按顺序评估条件的事实。
您应在具有多个查询的查询中限定所有所有列名。但是，这些列的来源尚不清楚。
根据您的原始逻辑（和高尔夫规则），handicap可能永远不会是负数，因此我很乐意删除该条件。

Answer 2

使用cte

with cte as
(
select  uu.Id, firstname, lastname, userhandicap, 
  case when userhandicap>=0 and userhandicap<=5 then '0-5'
  when userhandicap>=6 and userhandicap<=11 then '6-11' 
  when UserHandicap>=12 and UserHandicap<=18 then '12-18' 
  when UserHandicap>=19 and UserHandicap<=26 then '19-26'
  else '27 and above' end as range
  from dbo.[User] uu inner join dbo.[EventRegisteredUsers] eru
  on uu.Id = eru.UserId 
  where eru.UserId not in (Select fp.UserId from dbo.[FlightPlayer] fp 
  inner join dbo.[Flight] f
  on fp.FlightId = f.Id 
  where f.Rounds = '1'
  and f.Starthole = '0a9b926e-0baa-4369-8cf8-8fc84ca80d65' and f.EventId = 
  '7de10ad6-098d-419f-9c2d-2e62803ad1f7')
  and eru.EventId = '7de10ad6-098d-419f-9c2d-2e62803ad1f7'
), t2 as 
(
 select *,row_number() over(partition by range order by cast(userhandicap as int) rn from cte
) select * from t2 where rn<=3

如何在SQL中通过分区使用别名

2 个答案: