Vfrdtyky

I am new to the SQL. I am learning joins in query so that i eterive the information from the table using information. I am working in this question .

Get the EmployeeNumber for the employees and the date they started any given department.

Below is my table definition :

CREATE TABLE Employees (

    EmployeeID      int         IDENTITY(1,1) PRIMARY KEY

    ,EmployeeNumber int         UNIQUE

    ,DateOfBirth    datetime        NOT NULL

    ,FirstName      nvarchar(14)    NOT NULL

    ,MiddleName     nvarchar(14)    NOT NULL

    ,LastName       nvarchar(16)    NOT NULL

    ,DateHired      datetime        NOT NULL 

)



CREATE TABLE Customers (

    CustomerID      int         IDENTITY(1,1) PRIMARY KEY

    ,FirstName      nvarchar(14)    NOT NULL

    ,MiddleName     nvarchar(14)    NOT NULL

    ,LastName       nvarchar(16)    NOT NULL

    ,DateLastVisited datetime       NOT NULL 

    ,EmailAddress   nvarchar(52)    NOT NULL

)



CREATE TABLE Departments (

    DepartmentID    int         IDENTITY(1,1) PRIMARY KEY

    ,Code           nchar(4)        UNIQUE

    ,Name           nvarchar(40)    NOT NULL 

)



CREATE TABLE DepartmentEmployees (

    DepartmentEmployeeID    int     IDENTITY(1,1) PRIMARY KEY

    ,EmployeeID     int             NOT NULL

            CONSTRAINT Department_Employee REFERENCES Employees(EmployeeID)

    ,DepartmentID   int         NOT NULL

            CONSTRAINT Employee_Department REFERENCES Departments(DepartmentID)

    ,DateStarted    datetime        NOT NULL

    ,DateEnded      datetime        NOT NULL 

)



CREATE TABLE Salaries (

    SalaryID        int         IDENTITY(1,1) PRIMARY KEY

    ,EmployeeID     int         NOT NULL

            CONSTRAINT Salaried_Employee REFERENCES Employees(EmployeeID)

    ,Amount     money           NOT NULL

    ,DateStarts     datetime        NOT NULL

    ,DateEnds       datetime        NOT NULL 

)

I have added the information by inserting the data accordingly to the table.
For the question .
I have written this answer but i am not sure wether it is right or not.

  SELECT e.EmployeeNumber, 

         d.DateStarted 

    FROM Employees e

    Right 

     Join DepartmentEmployees d

       on e.EmployeeID= d.DepartmentEmployeeID;

DepartmentEmployeeID is the primary key for the table department, you need to join the employee id's in both tables.

SELECT E.EmployeeNumber, D.DateStarted 

FROM DepartmentEmployees D 

LEFT JOIN Employees E 

ON E.EmployeeID= D.EmployeeID;