我对此很新,所以原谅如果这已被张贴(我不知道甚至搜索什么)。使用总和()与多个where子句
我有2个表,会计和用法
AccountID AccountStartDate AccountEndDate
-------------------------------------------
1 12/1/2012 12/1/2013
2 1/1/2013 1/1/2014
UsageId AccountID EstimatedUsage StartDate EndDate
------------------------------------------------------
1 1 10 1/1 1/31
2 1 11 2/1 2/29
3 1 23 3/1 3/31
4 1 23 4/1 4/30
5 1 15 5/1 5/31
6 1 20 6/1 6/30
7 1 15 7/1 7/31
8 1 12 8/1 8/31
9 1 14 9/1 9/30
10 1 21 10/1 10/31
11 1 27 11/1 11/30
12 1 34 12/1 12/31
13 2 13 1/1 1/31
14 2 13 2/1 2/29
15 2 28 3/1 3/31
16 2 29 4/1 4/30
17 2 31 5/1 5/31
18 2 26 6/1 6/30
19 2 43 7/1 7/31
20 2 32 8/1 8/31
21 2 18 9/1 9/30
22 2 20 10/1 10/31
23 2 47 11/1 11/30
24 2 33 12/1 12/31
我想编写一个查询,让我估计使用情况每月(从现在开始,直到上个月我们所服务的帐户)的所有帐户在该月份提供服务。
结果将如下所示:
Month-Year Total Est Usage
------------------------------
Oct-12 0 (none being served)
Nov-12 0 (none being served)
Dec-12 34 (only accountid 1 being served)
Jan-13 23 (accountid 1 & 2 being served)
Feb-13 24 (accountid 1 & 2 being served)
Mar-13 51 (accountid 1 & 2 being served)
...
Dec-13 33 (only accountid 2 being served)
Jan-14 0 (none being served)
Feb-14 0 (none being served)
我假设我需要总结,然后做一组,...但真的不知道我怎么逻辑奠定想这一点。
使用日期应该有几年? – Laurence