sql 实现按月份，季度统计报表

呵呵，我们在处理设计到日期统计时候经常会按照年度，季度，月份统计进行同期比或者环比
先看看表结构

/****** 对象:  Table [dbo].[t_case_statistics]  作者：JC_Dreaming  脚本日期: 08/30/2010 11:53:15 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_PADDING ON
GO
CREATE TABLE [dbo].[t_case_statistics](
	[caseid] [bigint] IDENTITY(1,1) NOT NULL,
	[caseapplicant] [varchar](100) COLLATE Chinese_PRC_CI_AS NOT NULL,
	[casestartdate] [datetime] NULL
) ON [PRIMARY]

GO
SET ANSI_PADDING OFF

其中caseid 主键自增长，caseapplicant为申报人，casestartdate起始时间。
就按照起始时间进行统计。
插入几条测试语句

insert into t_case_statistics (caseapplicant,casestartdate) 
 values ('权限以上企业投资备案项目上报',convert(DATETIME,'2009-08-28 13:14:56',111));
insert into t_case_statistics (caseapplicant,casestartdate) 
 values ('一、二类机动车维修经',convert(DATETIME,'2009-08-28 14:11:09',111));
insert into t_case_statistics (caseapplicant,casestartdate) 
 values ('盟工商非公司企业',convert(DATETIME,'2009-08-28 14:16:10',111));
insert into t_case_statistics (caseapplicant,casestartdate) 
 values ('利用外国政府贷款',convert(DATETIME,'2010-08-27 15:13:12',111));
......

呵呵，我们看看数据库组织语句

select years as '年份',
case when months=1 then counts else 0 end '1月份',
case when months=2 then counts else 0 end '2月份',
case when months=3 then counts else 0 end '3月份',

case when quarters=1 then counts else  0 end '一季度',
case when months=4 then counts else 0 end '4月份',
case when months=5 then counts else 0 end '5月份',
case when months=6 then counts else 0 end '6月份',
case when quarters=2 then counts else  0 end '二季度',
case when months=7 then counts else 0 end '7月份',
case when months=8 then counts else 0 end '8月份',
case when months=9 then counts else 0 end '9月份',
case when quarters=3 then counts else  0 end '三季度',
case when months=10 then counts else 0 end '10月份',
case when months=11 then counts else 0 end '11月份',
case when months=12 then counts else 0 end '12月份',
case when quarters=4 then counts else  0 end '四季度'
from(
select datepart(yy,caseStartDate) as years,datepart(q,caseStartDate) as quarters, datepart(mm,caseStartDate) months,count(1)as counts 
from ximeng_web.dbo.t_case_statistics group by year(caseStartDate),datepart(q,caseStartDate),month(caseStartDate) 
)as test

其中month(caseStartDate) 等效于datepart(mm,caseStartDate)
year(caseStartDate)等效于 datepart(yy,caseStartDate)
可惜sql只提供了这两个统计函数，需要按照其它日期统计就不如datepart()灵活方便自如
统计效果：