T：SQL：从行中选择值作为列

我在行样式中有一个Profiles store配置文件属性值的表,例如：

[ProfileID]     [PropertyDefinitionID]      [PropertyValue]
1               6                           Jone
1               7                           Smith
1               8                           Mr
1               3                           50000

和另一个属性定义表：

[PropertyDefinitionID]  [PropertyName]
6                       FirstName
7                       LastName
8                       Prefix
3                       Salary

如何使用PIVOT或任何其他方式以这种方式显示它：

[ProfileID] [FirstName] [LastName]  [Salary]
1           Jone        Smith       5000

解决方法

没有PIVOT关键字,只需按分组即可轻松完成此操作

select
    P.ProfileID,min(case when PD.PropertyName = 'FirstName' then P.PropertyValue else null end) as FirstName,min(case when PD.PropertyName = 'LastName' then P.PropertyValue else null end) as LastName,min(case when PD.PropertyName = 'Salary' then P.PropertyValue else null end) as Salary
from Profiles as P
    left outer join PropertyDefinitions as PD on PD.PropertyDefinitionID = P.PropertyDefinitionID
group by P.ProfileID

您也可以使用PIVOT关键字执行此操作

select
    *
from
(
    select P.ProfileID,P.PropertyValue,PD.PropertyName
    from Profiles as P
        left outer join PropertyDefinitions as PD on PD.PropertyDefinitionID = P.PropertyDefinitionID
) as P
    pivot
    (
        min(P.PropertyValue)
        for P.PropertyName in ([FirstName],[LastName],[Salary])
    ) as PIV

更新：对于动态数量的属性 – 请查看Increment value in SQL SELECT statement