Pivoting Dates to Day of week - sql

Question

I'm currently trying to create a grid showing worked hours of employees.
Here's what my data look like (simplified) :
|ID |Client |Task |Hours |Date |
------------------------------------------
|1 |ABC |A |3 |09/06/2014|
|2 |ABC |A |5 |09/06/2014|
|3 |DEF |B |8 |10/06/2014|
|4 |DEF |C |8 |11/06/2014|
|5 |ABC |A |8 |12/06/2014|
And here's what the output must look like:
|Client |Task |Sun |Mon |Tue |Wed |Thu |Fri |Sat |
--------------------------------------------------
|ABC |A | |3 | | |8 | | |
|ABC |A | |5 | | | | | |
|DEF |B | | |8 | | | | |
|DEF |C | | | |8 | | | |
My problem is really close to this one. However there's a major diffrence: it's possible in my case to have multiple values for the same combination of Client-Task-Date.
As shown in the desired output, employees will sometime seperate their work hours even if they worked for the same client and on the same task and i can't use aggregate since all the data shown in the grid will be interactive to the end user.
Is there a way to obtain such output using pivot or any other SQL mechanics such as CASE WHEN ?

Answer 1

WITH t AS (
SELECT
Client,
Task,
Hours,
ROW_NUMBER() OVER(PARTITION BY Client,Task,Date ORDER BY Date) rn,
DATEPART(dw,date) DayOfWeek
FROM MyTable
)
SELECT Client, Task, [1] Sun, [2] Mon, [3] Tues, [4] Wed, [5] Thu, [6] Fri, [7] Sat
FROM t
PIVOT(SUM(Hours) FOR DayOfWeek IN ([1],[2],[3],[4],[5],[6],[7])) p