Question

您好我有一个关注查询，它将使用PIVOT函数

生成关注度报告

以下是程序：

declare  @in_date DATETIME       

/*Select all the stagign entries related to promotion id and investment type id */    
  /* also only those staging daat related interface status tracking*/

  -- Getting all distinct dates into a temporary table #Dates
    SELECT a.date as full_date_of_attendence INTO #Dates
    FROM dbo.getFullmonth(@in_date) a
    ORDER BY a.date



    -- The number of days will be dynamic. So building
    -- a comma seperated value string from the dates in #Dates
    SELECT  @cols = COALESCE(@cols + ',[' + CONVERT(varchar, full_date_of_attendence, 106)
                                    + ']','[' + CONVERT(varchar, full_date_of_attendence, 106) + ']')
    FROM    #Dates
    ORDER BY full_date_of_attendence


    --select @cols

    ---- Building the query with dynamic dates

SET @qry =
    'SELECT * FROM
    (SELECT admission_id, attendence_status , date_of_attendence
    FROM dbo.tblattendence)emp
    PIVOT (MAX(attendence_status) FOR date_of_attendence IN (' + @cols + ')) AS stat'    



    -- Executing the query
    EXEC(@qry)

    -- Dropping temporary tables
    DROP TABLE #Dates

这是上述查询::

的输出

admission_id    01 May 2013 02 May 2013 03 May 2013
2                NULL               1               0
3                NULL               1               1
4                NULL               0               0
5                NULL               0               1

在这里，我想将列的名称更改为01,02,03...... 我希望值1为“P”，0为“A”

任何人都可以帮助我实现这个目标吗？

Answer 1

我建议您对代码进行以下更改。如果你想要一个日期列表（1,2,3等），那么你可以使用DAY函数。

通常，当我动态获取列列表时，我的偏好是使用STUFF和FOR XML PATH，我会将该代码更改为以下内容：

select @colsPiv = STUFF((SELECT ',' + QUOTENAME(cast(day(full_date_of_attendence) as varchar(2))) 
                from #Dates
                GROUP BY full_date_of_attendence
                ORDER BY full_date_of_attendence
        FOR XML PATH(''), TYPE
        ).value('.', 'NVARCHAR(MAX)') 
    ,1,1,'')

然后，如果您要将0替换为A，将1替换为P，则需要创建查询以获取列列表替换值：

select @colsSel = STUFF((SELECT ', case when ' + QUOTENAME(cast(day(full_date_of_attendence) as varchar(2)))+'= 1 then ''P'' else ''A'' end as '+QUOTENAME(cast(day(full_date_of_attendence) as varchar(2)))
                      from #Dates
                      GROUP BY full_date_of_attendence
                      ORDER BY full_date_of_attendence
                FOR XML PATH(''), TYPE
                ).value('.', 'NVARCHAR(MAX)') 
                ,1,1,'')

基本上，这是创建一个类似于此的选择列表：

select case when [1] = 1 then 'P' else 'A' end as [1], ...

然后您的最终查询将是：

SET @qry =
'SELECT admission_id, '+@colsSel +' 
 FROM
 (
    SELECT admission_id, 
      attendence_status , 
      day(date_of_attendence) date_of_attendence
    FROM dbo.tblattendence
 )emp
 PIVOT 
 (
    MAX(attendence_status) 
    FOR date_of_attendence IN (' + @colsPiv + ')
 ) AS stat'

请参阅SQL Fiddle with Demo

Answer 2

让我们改变你想要的两件事，即

CONVERT(CHAR(2), full_date_of_attendence, 106) - 使用CHAR（2）代替varchar
CASE attendence_status when 1 then 'P' else 'A' END

具有最小更改的代码。希望这有助于您了解如何在将来对其他代码进行类似的更改。

declare @in_date DATETIME

/*Select all the stagign entries related to promotion id and investment type id */    
/* also only those staging daat related interface status tracking*/

-- Getting all distinct dates into a temporary table #Dates
SELECT a.date as full_date_of_attendence INTO #Dates
FROM dbo.getFullmonth(@in_date) a
ORDER BY a.date



-- The number of days will be dynamic. So building
-- a comma seperated value string from the dates in #Dates
SELECT  @cols = COALESCE(@cols + ',', '') + [' +
        CONVERT(CHAR(2), full_date_of_attendence, 106) + ']'
FROM    #Dates
ORDER BY full_date_of_attendence


--select @cols

---- Building the query with dynamic dates

SET @qry =
'SELECT * FROM
(SELECT admission_id, CASE attendence_status when 1 then 'P' else 'A' END, date_of_attendence
FROM dbo.tblattendence)emp
PIVOT (MAX(attendence_status) FOR date_of_attendence IN (' + @cols + ')) AS stat'    



-- Executing the query
EXEC(@qry)

-- Dropping temporary tables
DROP TABLE #Dates

从动态表中选择时更改列名称

2 个答案: