问题描述

首先感谢帮助过这个复杂难查询的朋友们.

First of all I would like to thank the friends who helped this complex and difficult query.

我有三张桌子

表一

 StaffId     FirstName       LastName   staffType
---------------------------------------
   1          Adam            Sorme      Student 
   2          Lara            Sandra     Teacher
   3          Jack            Jones      Student

表 2

 GateId   GateName  
 ---------------------------------------
   1        frontDoor
   2        superDoor

表 3

Id transitionDate     GateId  StaffId 
 ---------------------------------------
1  2018-01-1 08:00:00    1     1
2  2018-01-1 10:00:00    2     1
3  2018-01-1 20:00:00    2     1
4  2018-01-2 07:00:00    1     2
5  2018-01-2 10:00:00    1     3
6  2018-01-9 12:00:00    2     2

我想要学生每天的第一个和最后一个动作.如果在指定日期之间没有可用的移动，则必须将值设置为 null

I want the first and last movements of students for each day. Value must be set to null if no movement is available between the specified dates

transitionDate> '2018-01-1 00:00:00 000' 
 and transitionDate< '2018-01-03 00:00:00 000'

输出:

  Id     Date    MinTransitionDate    MaxTransitionDate    FirstGateName LastGateName    StaffId    StaffType
  1   2018-01-01  2018-01-1 08:00:00 2018-01-1 20:00:00    frontDoor      superDoor         1         Student
  2   2018-01-01  null                null                  null           null             3         student
  3   2018-01-02  null                null                  null           null             1         student
  4   2018-01-02  2018-01-2 10:00:00  null                 frontDoor       null             3         student

推荐答案

你可以试试像下面这样的查询

you can try a query like below

查看工作演示

create table staff(StaffId int,   FirstName  nvarchar(10),  LastName nvarchar(10),  staffType nvarchar(10))
insert into staff values
(1,'Adam','Sorme','Student') 
,(2,'Lara','Sandra','Teacher')
,(3,'Jack','Jones','Student')

go

create table gate(GateId int,  GateName  nvarchar(10))
insert into gate values
(1,'frontDoor')
,(2,'superDoor')

go
create table logs 
(Id int, transitionDate  datetime,   GateId  int, StaffId  int)
insert into logs values
(1,'2018-01-1 08:00:00',1,1)
,(2,'2018-01-1 10:00:00',2,1)
,(3,'2018-01-1 20:00:00',2,1)
,(4,'2018-01-2 07:00:00',1,2)
,(5,'2018-01-2 10:00:00',1,3)
,(6,'2018-01-9 12:00:00',2,2)
go
declare @startdate datetime, @enddate datetime
select @startdate='2018-01-1 00:00:00' , @enddate='2018-01-03 00:00:00'


; with tempSet as 
(
    select 
    transitionDatetime=l.transitionDate,
    gateName=g.gateName,
    staffid=l.staffid,
    idx=
         row_number() over(partition by l.staffid order by l.transitionDate ) -
        row_number() over(partition by l.staffid,cast(l.transitionDate as date) order by l.transitionDate ),
    transitionDate=cast(l.transitionDate as date)
    from
    logs l inner join staff s on
    l.staffid=s.staffid and staffType='Student'
    join gate g on g.gateid=l.gateid
)
, groupedSet as
(
    select 
    t1.*,
    FirstGateName=t2.gatename,
    lastGateName=t3.gatename
    from
    (
        select
        staffid,
        mintransitionDate=min(transitionDatetime),
        maxtransitionDate= case when count(1)>1 then max(transitionDatetime) else null end,
        transitionDate=max(transitionDate),
        idx
        from
        tempSet 
        group by staffid,idx
    ) t1
    left join
    tempSet t2
    on t1.idx=t2.idx 
    and t1.staffid=t2.staffid and t1.mintransitionDate=t2.transitionDatetime
     left join
    tempSet t3
    on t1.idx=t3.idx 
    and t1.staffid=t3.staffid and t1.maxtransitionDate=t3.transitionDatetime
    where t1.transitionDate between @startdate and @enddate
 )

 select
 t.*,
 g.mintransitionDate,
 g.maxtransitionDate,
 g.FirstGateName,
 g.LastGateName
 from 
 groupedSet g
 right join
 (
     select 
         d,
         staffid
     from
     (
         select 
         top  (select datediff(d,@startdate, @endDate))
         d=dateadd(d,row_number() over(order by (select null))-1, @startDate)
         from
         sys.objects o1 cross join sys.objects o2
     )tally
          cross join
     staff 
     where staff.stafftype='Student'
    )t
 on cast(t.d as date)=cast(g.transitionDate as date) and t.staffid=g.staffid
 order by t.d asc, t.staffid asc

这篇关于T-SQL 最大日期和最小日期值单行的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！