我有一种情况需要为员工的考勤卡分配适当的费率。无论费率如何，员工都会记录他们的时间（即在记录时间时不可用）。存储费率的系统将收到每日更新，费率可以在成本核算期内的任何时间点返回（追溯）。出于报告目的，我需要能够在特定日期报告费率。请考虑以下表格：
create table #timesheet (
txid int identity(1,1)
, empid int
, work_date datetime
, jobno varchar(16)
, hoursamt decimal(8,2)
)
create table #payrate (
txid int identity(1,1)
, empid int
, rate money
, eff_date datetime
, asof_date datetime
)
insert into #timesheet ( empid, work_date, jobno, hoursamt ) values ( 1, '2010-01-01', 'A', 8 )
insert into #timesheet ( empid, work_date, jobno, hoursamt ) values ( 1, '2010-01-02', 'A', 8 )
insert into #timesheet ( empid, work_date, jobno, hoursamt ) values ( 1, '2010-01-03', 'A', 8 )
insert into #timesheet ( empid, work_date, jobno, hoursamt ) values ( 1, '2010-01-04', 'A', 8 )
insert into #timesheet ( empid, work_date, jobno, hoursamt ) values ( 2, '2010-01-01', 'B', 8 )
insert into #timesheet ( empid, work_date, jobno, hoursamt ) values ( 2, '2010-01-02', 'B', 8 )
insert into #timesheet ( empid, work_date, jobno, hoursamt ) values ( 2, '2010-01-03', 'B', 8 )
insert into #timesheet ( empid, work_date, jobno, hoursamt ) values ( 2, '2010-01-04', 'B', 8 )
insert into #payrate ( empid, rate, eff_date, asof_date ) values ( 1, 10, '2010-01-01', '2010-01-01' ) -- Starting rate
insert into #payrate ( empid, rate, eff_date, asof_date ) values ( 1, 11, '2010-01-03', '2010-01-05' ) -- Retro active
insert into #payrate ( empid, rate, eff_date, asof_date ) values ( 2, 8, '2010-01-01', '2010-01-01' ) -- Starting rate
insert into #payrate ( empid, rate, eff_date, asof_date ) values ( 2, 9, '2010-01-03', '2010-01-02' ) -- Retro active date
insert into #payrate ( empid, rate, eff_date, asof_date ) values ( 2, 10, '2010-01-01', '2010-01-05' ) -- Retro active date
我想要一个接受一个参数（asof_date）的查询，该参数指示费率生效的日期。给定以下“asof”日期，相同的查询将返回以下结果。请注意，追溯活动更改会在payrate表中的'asof'日期生效。假设费率在通过payrate表中的条目更改之前有效。成本=费率*小时。日期为YYYY-MM-DD格式。这些注释仅供参考，不应在结果集中返回。
declare @asof datetime
set @asof = '2010-01-01'
----------------------------------------------------
empid | work_date | jobno | hoursamt | rate | cost | Notes
----------------------------------------------------
1 2010-01-01 A 8 10 80 Rate effective the 1st
1 2010-01-02 A 8 10 80
1 2010-01-03 A 8 10 80
1 2010-01-04 A 8 10 80
2 2010-01-01 B 8 8 64 Rate effective the 1st
2 2010-01-02 B 8 8 64
2 2010-01-03 B 8 8 64
2 2010-01-04 B 8 8 64
declare @asof datetime
set @asof = '2010-01-03'
----------------------------------------------------
empid | work_date | jobno | hoursamt | rate | cost | Notes
----------------------------------------------------
1 2010-01-01 A 8 10 80 Rate effective the 1st
1 2010-01-02 A 8 10 80
1 2010-01-03 A 8 10 80
1 2010-01-04 A 8 10 80
2 2010-01-01 B 8 8 64
2 2010-01-02 B 8 8 64
2 2010-01-03 B 8 9 72 Rate effective the 3rd
2 2010-01-04 B 8 9 72
declare @asof datetime
set @asof = '2010-01-06'
----------------------------------------------------
empid | work_date | jobno | hoursamt | rate | cost | Notes
----------------------------------------------------
1 2010-01-01 A 8 10 80
1 2010-01-02 A 8 10 80
1 2010-01-03 A 8 11 88 Rate effective the 3rd
1 2010-01-04 A 8 11 88
2 2010-01-01 B 8 10 80 Rate effective the 1st
2 2010-01-02 B 8 10 80
2 2010-01-03 B 8 10 80
2 2010-01-04 B 8 10 80
提前致谢！
答案 0 :(得分：1)
您可以使用outer apply搜索特定的付费率。此示例将outer apply与top 1组合在一起，以选择最近的付费率。
select t.empid
, t.work_date
, t.jobno
, t.hoursamt
, rate.rate
, t.hoursamt * rate.rate
from #timesheet t
outer apply
(
select top 1 *
from #payrate p
where p.empid = t.empid
and p.asof_date <= @asof
and p.eff_date <= t.work_date
order by
p.eff_date desc
) rate