sql - SQL SERVER中的select查询需要支持

Question

我有3张这样的桌子：

- Employee_Table (Employee_Number, Employee_Name, Department_Number) 
    With Employee_Number is PRIMARY KEY, Department_Number is FOREIGN KEY;

- Employee_Skill_Table (Employee_Number, Skill_Code, Date Registered) 
    With PRIMARY KEY (Employee_Number, Skill_Code);

- Department (Department_Number, Department_Name) 
    With PRIMARY KEY (Department_Number); 

我该如何指定

the departments which have >= 3 employees

帮我！

标签： sqlsql-serverselect

Answer 1

如果您只需要人数超过 3 人的部门，请尝试此查询

SELECT d.Department_Name
FROM Department d 
JOIN Employee_Table e ON e.Department_Number = d.Department_Number
GROUP BY Department_Name
HAVING COUNT(*) >= 3