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Relational Schema: Employee (EmployeeID, FirstName, LastName, Email, Phone, Hi...
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Relational Schema:
Employee (EmployeeID, FirstName, LastName, Email, Phone, HireDate, Salary, #DepartmentID)Department (DepartmentID, DepartmentName, #ManagerID)Project (ProjectID, ProjectName, StartDate, EndDate, Budget)Employee_Project (#EmployeeID, #ProjectID, Role, AssignmentDate)
Explanation of Relationships:
- Employee (EmployeeID) is the primary key.
- Department (DepartmentID) is the primary key.
- Project (ProjectID) is the primary key.
- Employee_Project (#EmployeeID, #ProjectID) is a composite primary key (many-to-many relationship between Employee and Project).
- Employee(#DepartmentID) REFERENCES Department(DepartmentID): An employee belongs to a department.
- Department(#ManagerID) REFERENCES Employee(EmployeeID): A manager is an employee.
- Employee_Project(#EmployeeID) REFERENCES Employee(EmployeeID)
- Employee_Project(#ProjectID) REFERENCES Project(ProjectID)
QUESTION
Which query displays the number of employees per department?A)SELECT COUNT(*) FROM Employee;B) SELECT DepartmentID, COUNT(*) FROM Employee;C) SELECT DepartmentID, COUNT(*) FROM Employee GROUP BY DepartmentID;D) SELECT DepartmentID, COUNT(*) FROM Employee HAVING COUNT(*) > 1;❌
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