Question

我有两个名为Emp和TrainingTable

的表

Emp列（EmpId(PK, int, not null), EmpName(nchar(10), null)）
TrainingTable列（EmpId(FK, int, null), TainingId(int, null), TainingName(nvarchar(50), not null)）

代码：

DECLARE @cols AS NVARCHAR(MAX),
@query  AS NVARCHAR(MAX)

select @cols = STUFF((SELECT ',' + QUOTENAME(TainingId) 
                from TrainingTable
                group by TainingId
                order by TainingId
        FOR XML PATH(''), TYPE
        ).value('.', 'NVARCHAR(MAX)') 
    ,1,1,'')

set @query = 'SELECT EmpName,' + @cols + ' from 
         (
            select Emp.EmpName, TainingName, TainingId
            from TrainingTable INNER JOIN Emp ON TrainingTable.EmpId = Emp.EmpId
        ) x
        pivot 
        (
            max(TainingName)
            for TainingId in (' + @cols + ')
        ) p '

execute(@query)

现在我要做的是使用Training1，Traning2，..等重命名列1,2,3 .. 结果表可能会根据数据而改变。列可能会增加..

我几乎尝试了所有事情......但没有找到正确的方法来实现它。

Answer 1

试试这个

您需要使用CAST（）

来转换列

        DECLARE @cols AS NVARCHAR(MAX),
        @query  AS NVARCHAR(MAX)

select @cols = STUFF((SELECT ',' + QUOTENAME('Training' + CAST(TainingId AS Varchar(50))) 
                        from TrainingTable
                        group by TainingId
                        order by TainingId
                FOR XML PATH(''), TYPE
                ).value('.', 'NVARCHAR(MAX)') 
            ,1,1,'')

        set @query = 'SELECT EmpName,' + @cols + ' from 
                 (
                    select Emp.EmpName, 
                           TainingName,
                           col = ''Training'' + cast(TainingId as varchar(10))
                    from TrainingTable 
                    INNER JOIN Emp ON TrainingTable.EmpId = Emp.EmpId
                ) x
                pivot 
                (
                    max(TainingName)
                    for col in (' + @cols + ')
                ) p '

        execute(@query)

Refer

如何使用结果表的前缀重命名列，使用数据透视查询获取结果表

1 个答案: