Question

我们有一个像

这样的员工表

Employee ID
Name

EmployeeManager表，如

employeeid
employeeManagerid
intyear
intperiod

因此每个经理都是员工，employeemanagerid是员工表中的forigen键，而且是员工表中的employeeid

员工可以在一年内拥有多名经理 intYear和intPeriod，intPeriod是月份，因此它的值为1-12

我想要实现的目标是，如果一个经理人在一个时期（几个月）内被选中，并且没有经理被分配到接下来的三个时期（月），那么同一个经理将被分配给那个人，

举个例子

employee table
----------------------------------------------------------------
employeeid   name
1              a
2              b
3              c
4              d
5              e
-------------------------------------------------------------------

EmployeeManager table
----------------------------------------------------------------------
employeeid           employeemanagerid       intyear         intperiod
-----------------------------------------------------------------------
1                           5                   2017            3
1                           4                   2017            4
2                           4                   2017            6
3                           4                   2017            6
------------------------------------------------------------------------

我的查询

select e.name,e.employeeid
from employee e
left join employeemanager em
on e.employeeid = em.employeeid
where
em.employeemanagerid  = @managerid
and em.intyear = @intyear
and em.intperiod <= @intperiod

the values supplied as a parameter are
@managerid = 4
@intyear = 6
@intperiod = 2017

我想要的预期结果是

------------------------------------------------------
name               employeeid               
a                   1
b                   2
c                   3  
------------------------------

员工b，c是直接匹配，但是在第4期中设置了经理仍然持续到第6期

我应该在查询中更改以获得此结果参数值从c＃发送。

Answer 1

问题是您是否过滤掉了不适合特定经理的所有记录，但您仍然希望这些记录会影响结果。你也没有做任何事情来阻止重复，如果你有一个员工从经理4到5到4，它会显示两次。您需要先获取一个查询，确定所需时间段内每行的正确经理是谁，然后从第一个查询中执行主查询。一种方法是：

--This gets all manager records for the period (or before), with a rowno added 
--sorted so that the most recent manager is always number 1
With emData as 
(
    Select employeeid, employeeManagerid, intyear, intperiod
      , ROW_NUMBER() OVER(Partition by employeeid ORDER BY intyear DESC, intperiod DESC) as RowNo
    from employeemanager
    where intyear <= @intyear 
        and intperiod <=@intperiod
)
--This is your original query, changed to use the above as the source
select e.name,e.employeeid
from employee e inner join 
emData em on e.employeeid = em.employeeid
where
em.employeemanagerid  = @managerid
and em.RowNo = 1  --THIS MAKES SURE YOU ARE ONLY LOOKING AT THE MOST RECENT MANAGER

从另一个时期的经理那里获得员工

1 个答案: