Question

我有三个表，如下所示：

1。 kit_test tk

tk.id  tk.first_name  tk.last_name  tk.dob     tk.registered_dt
SD007  Aarushi        Sharma        2/23/1987  10/5/2020
SD008  Camden         Howard        8/22/1993  10/6/2020

2。 employee_badged emp

emp.firstname   emp.lastname    emp.ssno    emp.empid
 Aarushi        Sharma          5175        570
 Camden         Howard          23513       804

3。 event_badged事件

events.empid    events.event_time_utc
   570              10/5/2020
   570              10/6/2020
   570              10/7/2020
   570              10/8/2020
   804              10/15/2020
   804              10/16/2020

这是我想要的输出。

regname     firstname    lastname   registered_date enterdate      count
Aarushi Sharma  Aarushi Sharma   10/5/2020      10/5/2020         1
Aarushi Sharma  Aarushi Sharma   10/5/2020      10/6/2020         1
Aarushi Sharma  Aarushi Sharma   10/5/2020      10/7/2020         1
Aarushi Sharma  Aarushi Sharma   10/5/2020      10/8/2020         1
Aarushi Sharma  Aarushi Sharma   10/5/2020      10/9/2020   
Aarushi Sharma  Aarushi Sharma   10/5/2020      10/10/2020  
Camden Howard   Camden  Howard   10/6/2020

这是我到目前为止的查询：

select distinct tk.first_name + ' ' + tk.last_name as "regname", EMP.FIRSTNAME, EMP.LASTNAME,
    trunc(tk.registered_dt) as registered_date,
    trunc(EVENTS.EVENT_TIME_UTC) as enterdate
    
    FROM kit_test as tk
    left join employee_badged emp
    ON tk.first_name + ' ' + tk.last_name=emp.FIRSTNAME + ' ' + emp.LASTNAME
    
    left join event_badged events
    ON EVENTS.EMPID=EMP.ID
    
    where
    date(tk.registered_dt) between '2020-10-05' and '2020-10-10'
    and (trunc(EVENTS.EVENT_TIME_UTC)  between '2020-10-05' and '2020-10-10') ;

我正在RedShift / Dbeaver / PostgreSQL上执行此任务。

Answer 1

我相信您应该首先左移两个事件表，然后左移被测雇员与结果子查询。

类似这样的东西（我无法测试它，因此可能对此查询执行一些更正操作）

select distinct tk.first_name + ' ' + tk.last_name as "regname", emp_events.FIRSTNAME, emp_events.LASTNAME,
trunc(tk.registered_dt) as registered_date,
trunc(emp_events.EVENT_TIME_UTC) as enterdate

FROM kit_test as tk
left join (

   select emp_badges.firstname, emp_badges.lastname events.event_time_utc
   from  employee_badged emp_badges
   left join event_badged events
   ON EMP_badges.ID=EVENTS.EMPID
   where
    (trunc(EVENTS.EVENT_TIME_UTC)  between '2020-10-05' and '2020-10-10') 
) emp_events

ON tk.first_name + ' ' + tk.last_name=emp_events.FIRSTNAME + ' ' + emp_events.LASTNAME
where
date(tk.registered_dt) between '2020-10-05' and '2020-10-10';

也许您不能这样做，但是在kit_test表中添加employee_id将大大改善表和查询设计

左联接时如何联接表不会为日期生成空值

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