Question

我想知道是否有人可以帮助我。以下是我的数据样本集：

FirstName   LastName   Department  Comment       DateWorked
Bob         Smith      Sleeves                  2017-01-01
Jim         Bo         Sleeves                  2017-01-01
Janet       Moore      Lids        No Show      2017-01-01
Jon         Bob        Lids                     2017-01-01

Bob         Smith      Mugs                     2017-01-02

Bob         Smith      Sleeves                  2017-01-03
Jim         Bo         Sleeves                  2017-01-03
Janet       Moore      Lids                     2017-01-03
Jon         Bob        Lids                     2017-01-03

应该返回这样的内容：

DateWorked  Department  HeadCount
2017-01-01  Sleeves     2
2017-01-01  Lids        2
2017-01-02  Mugs        1
2017-01-03  Sleeves     2
2017-01-03  Lids        2

到目前为止，我已尝试过一些事情。

这就是我想要的但它不起作用

SELECT Count(Distinct(FirstName, LastName, Department, Scheduled), Notes)  FROM Employees
Where Scheduled < 20171231
and Scheduled > 20170101
Group by Scheduled, Department, FirstName, LastName, Department, Comment

这只是给了我一个数字。

select count(*)
from
  (select count(*) CT
   from Employees
   group by Scheduled, Department) TD

这个错误了。

SELECT COUNT(DISTINCT FirstName, LastName, Department) FROM Employees

有人可以帮忙吗？感谢

Answer 1

您似乎想要：

SELECT DateWorked, Department, COUNT(*) as HeadCount
FROM Employees
WHERE Scheduled < 20171231 AND Scheduled > 20170101
GROUP BY DateWorked, Department
ORDER BY DateWorked, Department;

上面的内容会保留您在查询中的日期比较，尽管它们看起来不对。

我建议将日期比较写为：

SELECT DateWorked, Department, COUNT(*) as HeadCount
FROM Employees
WHERE  Scheduled >= '2017-01-01' AND Scheduled < '2017-12-31'
GROUP BY DateWorked, Department
ORDER BY DateWorked, Department;

这会修复日期比较，使其与您想要的结果更加一致。

您没有指定数据库。 YYYY-MM-DD是ISO标准日期格式，适用于大多数数据库。

Answer 2

SELECT DateWorked, Department, COUNT(*) AS HeadCount 
FROM Employees
WHERE Scheduled < 20171231 AND Scheduled > 20170101 
GROUP BY Department, DateWorked

通过（我认为）选择组的多个区别

2 个答案: