计算SQL中值的总和,以显示每月名称

Question

我有一个具有以下布局的表格.

Email Blast Table

EmailBlastId |  FrequencyId | UserId
---------------------------------
1            |   5          |   1
2            |   2          |   1
3            |   4          |   1


Frequency Table

Id | Frequency 
------------
 1 |  Daily
 2 |  Weekly
 3 |  Monthly
 4 |  Quarterly
 5 |  Bi-weekly

我需要在我的asp.net页面上提供一个网格显示,如下所示.

Email blasts per month.

UserId | Jan | Feb | Mar | Apr |..... Dec | Cumulative
-----------------------------------------------------
1        7      6     6     7          6     #xx

我能想到这样做的唯一方法如下,每个月都有一个案例陈述.

select SUM(
        CASE WHEN FrequencyId = 1 THEN 31 
        WHEN FrequencyId = 2 THEN 4
        WHEN FrequencyId = 3 THEN 1
        WHEN FrequencyId = 4 THEN 1
        WHEN FrequencyId = 5 THEN 2 END) AS Jan, 
      SUM(
        CASE WHEN FrequencyId = 1 THEN 28 (29 - leap year)
        WHEN FrequencyId = 2 THEN 4
        WHEN FrequencyId = 3 THEN 1
        WHEN FrequencyId = 4 THEN 0
        WHEN FrequencyId = 5 THEN 2 END) AS Feb, etc etc
FROM EmailBlast 
Group BY UserId

还有其他更好的方法吗？