我有一个表，其中有一列类型为 DateTime, 我想以 datetime 列为中心，以便日期显示为列(如星期一、星期二等).

I have table that has a column of type DateTime, I would like to pivot on the datetime column so that the dates are displayed as columns (as days of the week Monday, Tuesday etc).

例如，我有一个这样的表(不记得 SQL Server 是如何显示完整日期时间的，但你明白了):

So for example I have a table like this (can't remember how SQL Server displays full datetimes but you get the idea):

BugNo | DateOpened | TimeSpent

1234  | 16/08/2010 | 1.0 
4321  | 16/08/2010 | 3.5 
9876  | 17/08/2010 | 1.5 
6789  | 18/08/2010 | 7.0 
6789  | 19/08/2010 | 6.5 
6789  | 20/08/2010 | 2.5

我想以 DateOpened 列为中心来创建这样的结果集

I would like to pivot on the DateOpened column to create a result set like this

|TimeSpentOnBugByDay|  Mon  |  Tue  | Wed | Thu  | Fri | Sat | Sun
1234                    1
4321                    3.5
9876                           1.5
6789                                   7.0
6789                                         6.5
6789                                                2.5

我应该指出，我一次只能检索一个星期.

I should point out that I'll only be retrieving one week at a time.

我不确定这是否可能，但我很确定我以前见过类似的东西(不是我写的).

I'm not sure if this is possible, though I'm pretty certain I have seen something like this before (that I didn't write).

推荐答案

你可以这样做

SELECT BugNo, [Monday], [Tuesday], [Wednesday], [Thursday], [Friday], [Saturday], [Sunday]
FROM (
    SELECT BugNo, DATENAME(dw, DateOpened) AS DayWeek, TimeSpent
    FROM Bugs
    ) AS src
    pivot (
        SUM(TimeSpent) FOR DayWeek IN ([Monday], [Tuesday], [Wednesday], [Thursday], [Friday], [Saturday], [Sunday])
    ) AS pvt