Question

我的数据集如下所示：

emplid region location sub_dept dept start_dt end_dt     days
------ ------ -------- -------- ---- -------- ---------- ----
123456 East   NY       A           1 7/1/2005 9/30/2005    91
123456 East   NY       B           1 7/1/2012 11/9/2012   131
123456 West   San Jose C           2 7/1/2013 12/31/2013  183
123457 East   NY       B           1 7/1/2017 9/7/2017     68
123457 East   NY       B           1 7/1/2005 12/31/2005  183
123458 East   NY       B           1 7/1/2017 9/7/2017     68
123458 West   San Jose C           2 7/1/2010 7/31/2010    30
123459 East   NY       A           1 7/1/2017 9/7/2017     68
123460 East   Boston   F           3 7/1/2007 11/30/2007  152

我需要能够从最短日期开始为每月的第1天获取快照。因此，在示例中，最小日期为9/30/2005。所以我需要知道department/sub_dept/location/region每个10/1/2005, 11/1/2005 , 12/1/2005在uber-jar一直到最大日期。

Answer 1

您没有提到员工表的名称，所以我称之为employee_table。以下查询（或非常接近它的内容）应该生成您想要的内容：

With report_limits as (
      Select Trunc(min(start_dt), 'MONTH') as min_rpt_dt, 
             Trunc(max(end_dt), 'MONTH') as max_rpt_dt 
        From employee_table),
     report_dates as (
      Select add_months(min_rpt_dt, level-1) as rpt_dt
        From report_limits 
     Connect By add_months(min_rpt_dt, level-1) <= max_rpt_dt)
--
Select e.emplid, e.region, e.location, e.sub_dept, e.dept,
       e.start_dt, e.end_dt, e.days, r.rpt_dt
From report_dates r
Inner Join employee_table e on r.rpt_dt Between e.start_dt And e.end_dt
Order By r.rpt_dt, e.emplid;

report_limits查询确定报告日期的范围，report_dates查询使用Connect By子句生成范围内的一组日期，主查询将日期列表连接到员工日期。

Answer 2

尝试此查询：

 Declare @StartDate date='2005-09-29',
 @EndDate date='2017-04-01'

Select *,
Dateadd(mm, Datediff(mm, 0, date), 0) AS FirstDateOfMonth  from TableName
where   date >=@StartDate and date<=@EndDate

在每个月的第一天获取快照

2 个答案: