Oracle SQL-不一致的查询结果

我正在尝试编写一个Oracle SQL查询，该查询基于employeeID选择某个日期范围（每个employeeID的范围不同），然后对该日期范围内每个员工的特定绩效指标数字求和。对于同一个员工ID，我似乎得到了不一致的结果，这取决于我选择它的方式。我的问题是：

select c.employeeID, b.assessmentDate, c.startDate, c.endDate,
sum(case when employeeProductivityMetric='15' then 1 else 0 end) as Metric1,
sum(case when employeeProductivityMetric='20' then 1 else 0 end) as Metric2
from assessmentTable b 
inner join performanceMetricTable c on b.badgeID = c.badgeID
where b.assessmentDate between c.startDate and c.endDate
group by c.employeeID, b.assessmentDate, c.startDate, c.endDate
order by c.employeeID, b.assessmentDate;

请注意，给定的employeeID可以与多个badgeID关联

当我通过在where子句中添加以下内容来选择一个特定的employeeID（例如，2）时：

where c.employeeID=2

我得到了Metric1和Metric2的一些特定数字：

employeeID  assessmentDate  startDate   endDate    Metric1  Metric2
2           02-Jul-15       01-Jul-15   31-Jul-15  4        5

然而，当我

where c.employeeID between 1 and 3

我为员工2得到了不同的数字，比如：

employeeID  assessmentDate   startDate  endDate    Metric1  Metric2
2           02-Jul-15        01-Jul-15  31-Jul-15  3        0

有人知道为什么会这样吗？我的查询设计有问题吗

谢谢你的指点

---

Natalia

您可以通过检索详细记录来调试此类情况：

尝试比较以下查询

-- matched records for employeeID=2
select c.employeeID, c.badgeID, b.assessmentDate, c.startDate, c.endDate,
employeeProductivityMetric
from assessmentTable b 
inner join performanceMetricTable c on b.badgeID = c.badgeID
where b.assessmentDate between c.startDate and c.endDate
      and c.employeeID=2
order by c.employeeID, c.badgeID, b.assessmentDate;

及

---

很可能，您会注意到每个查询返回的

badgeID

中存在差异。

是否有可能

badgeID

链接到多个

employeeID

上？您是按

employeeID

分组的。对于给定的值，我看不出该列上的过滤条件会如何影响行内的结果。

-- matched records for employeeID between 1 and 3
select c.employeeID, c.badgeID, b.assessmentDate, c.startDate, c.endDate,
employeeProductivityMetric
from assessmentTable b 
inner join performanceMetricTable c on b.badgeID = c.badgeID
where b.assessmentDate between c.startDate and c.endDate
      and c.employeeID between 1 and 3
order by c.employeeID, c.badgeID, b.assessmentDate