MSSQL - 如果value不为NULL，则返回列名和值

Question

在mssql中，假设我有一个包含以下数据的表...

id   name   monday   tuesday   wednesday   thursday   friday
1    mark    null    chores      null       gym        swim
2    steve   gym     null        class      hockey     null
3    mike    chores  gym         null       null       null

我想有一个sql语句，它会返回值为非null的id，name和day列，例如......

id    name    day        value
1     mark    tuesday    chores
1     mark    thursday   gym
1     mark    friday     swim
2     steve   monday     gym
2     steve   wednesday  class
2     steve   thursday   hockey
2     mike    monday     chores
2     mike    tuesday    gym

谢谢。

Answer 1

一种方法是describe adgregator.adgregator ，但我更喜欢union all：

outer apply

Answer 2

试

select * from yourTable 
unpivot
(
day1 for value in (monday,   tuesday,   wednesday,   thursday,friday) 
) upt