根据不存在/不存在的 ID 查找记录

Question

当员工没有时间输入到名为employee_time et 的表中的时间卡中时，我需要报告。

我的问题是找到没有进入该周时间的人。

我使用 NOT IN 来查找表中不存在的员工 ID，因此如果记录不存在，则没有输入时间。这很好用。

Select
     e.userName,
     et.dateStart,
     et.dateEnd

From  employee_time et,
      employee e
Where
      e.employee_id NOT IN (Select employee_id from employee_time
                            where et.dateStart = date and
                                  et.end_date = date)
Group by 
      e.userName,
      et.startDate,
      et.endDate

问题出在应用程序中，当一个人导航到员工时间输入页面时，它会为员工创建一条记录，如果员工没有输入任何时间，则结果是零小时的记录。但该记录现在确实存在。因此在上面的查询中不会找到，我用下面的方法找到了totals = 0的记录

Select
     e.userName,
     et.dateStart,
     et.dateEnd,
     SUM(et.hoursTotal) AS total

From  employee_time et,
      employee e
Where
      e.employee_id = et.employee_id and
      et.hours_total = 0
Group by 
      e.userName,
      et.startDate,
      et.endDate

这也很有效，但是我需要嫁给他们，但迄今为止没有成功。你能帮忙吗？

Answer 1

一般格式如下：

Select employee_id
  From employee
Minus
Select employee_id
  From TableExpressionEliminatesOnMissingDates
Minus
Select employee_id
  From TableExpressionEliminatesOnSummarization;

Answer 2

我会这样写：

Select e.userName
From employee e
Where e.employee_id NOT IN (Select employee_id
                            from employee_time
                            where et.dateStart = $date and
                                  et.end_date = $date and 
                                  et.hoursTotal > 0
                           );

您从日期开始作为输入，所以我不明白为什么您在输出中也需要它。如果你这样做，我会选择：

Select e.userName, w.*
From employee e cross join
     (select distinct et.dateStart, et.end_date
      from employee_time et
      where $date between et.dateStart and et.dateEnd
     ) w
Where e.employee_id NOT IN (Select et.employee_id
                            from employee_time et
                            where $date between et.dateStart and et.dateEnd and
                                  et.hoursTotal > 0
                           );

注意：避免在外部查询中使用GROUP BY 会提高性能。

Answer 3

Select
     e.userName,
     et.dateStart,
     et.dateEnd,
     SUM(et.hoursTotal) AS total

From  
      employee e left outer join employee_time et on (e.employee_id = et.employee_id)
 -- Where nvl(et.hours_total,0) = 0
Group by 
      e.userName,
      et.startDate,
      et.endDate
having SUM(et.hoursTotal) > 0

如果你不想让你可以在应该相同的地方使用注释

如果你只想要employee_ids：

select e.empolyee_id 
from employee e left outer join employee_time et on (e.employee_id = et.employee_id)
Where nvl(et.hours_total,0) = 0;

Answer 4

以下查询查找在给定开始和结束日期的employee_time 中没有有效条目的所有员工：

select * 
from employee
where employee_id not in
(
  select employee_id 
  from employee_time
  where datestart = :date_start
    and end_date = :date_end
    and hours_total > 0
);