在SQL Server 2005中透视表以多次包含相同的列

Question

我需要透过以下名为tblGameRoleName的表 -

Game        Role    Name
VolleyBall  Coach   Sujatha
VolleyBall  Player  Rajendran
VolleyBall  Player  Juno
VolleyBall  Player  Indira
VolleyBall  Player  Ganesh
VolleyBall  Player  Vasanth
Tennis      Coach   Rajeshkumar
Tennis      Player  Vivek
Tennis      Player  Rubala

到下面有多次'Player'列的表 -

Game        Coach       Player1     Player2 Player3 Player4 Player5
VolleyBall  Sujatha     Rajendran   Juno    Indira  Ganesh  Vasanth
Tennis      Rajeshkumar Vivek       Rubala  NULL    NULL    NULL

问题是"玩家"的数量可以针对不同的"游戏"增加,结果表应该显示所有游戏的所有玩家.例如 - 如果我将以下'板球'团队添加到此表中 -

Cricket Coach   Gary
Cricket Player  Viru
Cricket Player  Gauti
Cricket Player  Sachin
Cricket Player  Mahi
Cricket Player  Yuvi
Cricket Player  Suresh
Cricket Player  Virat
Cricket Player  Bhajji
Cricket Player  Zaheer
Cricket Player  Ishant
Cricket Player  Ashish

然后结果表应显示11个播放器列.

这可以通过PIVOT功能实现吗？如果没有,请建议正确的方法来实现结果表.

Answer 1

这在前端报告/显示应用程序中可能更容易，但对于 sql，您需要执行动态透视。但由于这些列由连续的玩家编号作为别名，并且特定玩家因游戏而异，因此您无法使用典型的动态 SQL 示例。

这是一种方法：

样本数据

set ansi_warnings off
set nocount on
create table #t (Game varchar(20), Role varchar(15), [Name] varchar(20))
insert #t
          select 'VolleyBall', 'Coach', 'Sujatha'
union all select 'VolleyBall', 'Player', 'Rajendran'
union all select 'VolleyBall', 'Player', 'Juno'
union all select 'VolleyBall', 'Player', 'Indira'
union all select 'VolleyBall', 'Player', 'Ganesh'
union all select 'VolleyBall', 'Player', 'Vasanth'
union all select 'Tennis', 'Coach', 'Rajeshkumar'
union all select 'Tennis', 'Player', 'Vivek'
union all select 'Tennis', 'Player', 'Rubala'
union all select 'Cricket', 'Coach', 'Gary'
union all select 'Cricket', 'Player', 'Viru'
union all select 'Cricket', 'Player', 'Gauti'
union all select 'Cricket', 'Player', 'Sachin'
union all select 'Cricket', 'Player', 'Mahi'
union all select 'Cricket', 'Player', 'Yuvi'
union all select 'Cricket', 'Player', 'Suresh'
union all select 'Cricket', 'Player', 'Virat'
union all select 'Cricket', 'Player', 'Bhajji'
union all select 'Cricket', 'Player', 'Zaheer'
union all select 'Cricket', 'Player', 'Ishant'
union all select 'Cricket', 'Player', 'Ashish'

创建动态 SELECT 和 PIVOT 子句以及 EXEC 语句

declare @max int
select top 1 @max = count(*)
from #t 
where role = 'player' 
group by game 
order by count(*) desc

declare @sel varchar(2000)
       ,@piv varchar(2000)

;with nos (n) as (select 1 union all select n+1 from nos where n < @max)
select @sel = coalesce(@sel + ', ' 
       + 'max([' + convert(varchar(2), n) + ']) as player' + convert(varchar(2), n)
       , 'max([' + convert(varchar(2), n) + ']) as player' + convert(varchar(2), n)
       )

       ,@piv = coalesce(@piv + ',[' + convert(varchar(2), n) + ']', '[' + convert(varchar(2), n) + ']')
from   nos
-----------------------------------------------------------------------------

exec('
select p.game
       ,max(p.coach) as coach
       ,' + @sel + '
from   (
       select game
              ,case when role = ''coach'' then [name] end as coach
              ,case when role = ''player'' then [name] end as player
              ,row_number() over (partition by game, role order by name) as seq
       from   #t
       ) d
pivot (max(player) for seq in (' + @piv + ')) p
group by p.game
')

go
drop table #t

输出：

game                 coach                player1              player2              player3              player4              player5              player6              player7              player8              player9              player10             player11
-------------------- -------------------- -------------------- -------------------- -------------------- -------------------- -------------------- -------------------- -------------------- -------------------- -------------------- -------------------- --------------------
Cricket              Gary                 Ashish               Bhajji               Gauti                Ishant               Mahi                 Sachin               Suresh               Virat                Viru                 Yuvi                 Zaheer
Tennis               Rajeshkumar          Rubala               Vivek                NULL                 NULL                 NULL                 NULL                 NULL                 NULL                 NULL                 NULL                 NULL
VolleyBall           Sujatha              Ganesh               Indira               Juno                 Rajendran            Vasanth              NULL                 NULL                 NULL                 NULL                 NULL                 NULL