SQLpivot/Unpivot？

Question

真的希望有人能帮助我，我有一个 table 结构如下：

检索此数据的查询是：

SELECT

[Pattern Number]
,Sunday
,Monday
,Tuesday
,Wednesday
,Thursday
,Friday
,Saturday

FROM Access.Pattern_Details
WHERE [Pattern Number] = 4

+----------------+--------+--------+---------+-----------+----------+--------+----------+
| Pattern Number | Sunday | Monday | Tuesday | Wednesday | Thursday | Friday | Saturday |
+----------------+--------+--------+---------+-----------+----------+--------+----------+
|              4 |      0 |      1 |       1 |         1 |        1 |      1 |        0 |
+----------------+--------+--------+---------+-----------+----------+--------+----------+

我希望看起来像这样：

+----------------+------------+-----------+
| Pattern Number | WorkingDay |    Day    |
+----------------+------------+-----------+
|              4 |          0 | Sunday    |
|              4 |          1 | Monday    |
|              4 |          1 | Tuesday   |
|              4 |          1 | Wednesday |
|              4 |          1 | Thursday  |
|              4 |          1 | Friday    |
|              4 |          0 | Saturday  |
+----------------+------------+-----------+

我已经尝试了 PIVOT/UNPIVOT，这感觉是正确的方向，但我真的很纠结如何得到结果:(

Answer 1

在SQL服务器中，我会推荐cross apply和values()：

select pd.[Pattern Number], x.*
from Access.Pattern_Details pd
cross apply (values 
    ('Sunday',    Sunday), 
    ('Monday',    Monday),
    ('Tuesday',   Tuesday),
    ('Wednesday', Wednesday),
    ('Thursday',  Thursday),
    ('Friday',    Friday),
    ('Saturday',  Saturday)
) x(day, workingDay)
where pd.[Pattern Number] = 4

Answer 2

您可以使用 UNPIVOT:

SELECT [Pattern Number], [Working Day], [Day] 
FROM
(
  SELECT 4 [Pattern Number], 0 Sunday, 1 Monday, 1 Tuesday, 1 Wednesday, 1 Thursday, 1 Friday, 0 Saturday
) pvt
UNPIVOT([Working Day] FOR [Day] IN ([Sunday], [Monday], [Tuesday], [Wednesday], [Thursday], [Friday], [Saturday])) unpvt

db<>fiddle

UNPIVOT 有很好的记录和解释。参见：Using Pivot and Unpivot - SQL Server

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