Question

我有两个名为Employees的表，一个名为Shop。 Employees表保存所有员工的性别，而Shop表具有每个员工工作的商店的名称。

我需要计算男性和女性员工的数量，并将他们分组到他们工作的商店。例如，想要的结果将如下所示：

FemaleEmployees MaleEmployees Store 1 2 Ed's Hardware 3 4 Grocery store

到目前为止，我有这个：

SELECT COUNT(Gender) AS FemaleEmployees, StoreName AS Store
FROM Employees 
JOIN Store
ON Employees.EmployeeID = Store.EmployeeID
Where Gender = 'F'
GROUP BY StoreName;

SELECT COUNT(Gender) AS MaleEmployees, StoreName AS Store
FROM Employees
JOIN Store
ON Employees.EmployeeID = Store.EmployeeID
Where Gender = 'M'
GROUP BY StoreName;

这显然在两个选择查询中提供了所需的答案，但我需要它在一个查询中。我只需要帮助将两者合并为一种查询格式。

我已经尝试过使用两个subquerys，但到目前为止还没有任何效果。我知道如何得到答案，而不是所需的格式。如果有人能帮我解决这个问题，我将不胜感激。

Answer 1

你可以这样做

SELECT SUM(CASE WHEN Gender='F' THEN 1 ELSE 0 END) As FemaleEmployees,
       SUM(CASE WHEN Gender='M' THEN 1 ELSE 0 END) As MaleEmployees,
       storeName
FROM Employees 
JOIN Store
ON Employees.EmployeeID = Store.EmployeeID
GROUP BY storeName

Answer 2

使用COUNT

的另一种方法

SELECT COUNT(CASE WHEN Gender='F' THEN 1 END) As FemaleEmployees,
       COUNT(CASE WHEN Gender='M' THEN 1 END) As MaleEmployees,
       StoreName AS Store
FROM Employees 
JOIN Store
ON Employees.EmployeeID = Store.EmployeeID
Where Gender in ( 'F','M' )
GROUP BY StoreName;

过滤Gender子句中的Where，使查询效率不高..

Answer 3

你需要使用“case”语句来区分这些情况，如下所示： SELECT SUM (SELECT CASE WHEN GENDER = 'M' THEN 1 ELSE 0 END) as MaleCount, SUM (SELECT CASE WHEN GENDER = 'F' THEN 1 ELSE 0 END) AS FemaleCount, Storename AS Store FROM Employees JOIN Store ON Employees.EmployeeID = Store.EmployeeID



GROUP BY StoreName;

GROUP BY StoreName;

Answer 4

以上大多数答案总是得到性别1或0的计数......没有得到实际数量.. 因此，你可以做到这一点......

选择（如果GENDER =＆＃39; M＆＃39;那么COUNT（GENDER）ELSE 0 END）作为MaleCount，（例如，当性别=＆＃39; F＆＃39;那么（COENDER）ELSE 0 END）作为FemaleCount， Storename AS Store 来自员工加入商店 ON Employees.EmployeeID = Store.EmployeeID GROUP BY StoreName;

如何在SQL中的同一列中有两个COUNT个查询GROUPED？

4 个答案: