Cuvântul cheie RIGHT JOIN returnează toate înregistrările din tabelul din dreapta (tabelul 2) și înregistrările corespunzătoare din tabelul din stânga (tabelul 1).
Rezultatul va fi 0 înregistrări din stânga dacă nu există nicio potrivire.
SELECT column_name(s)
FROM table1
RIGHT JOIN table2
ON table1.column_name = table2.column_name
În acest tutorial vom folosi celebrul exemplu de bază de date „Northwind”.
Mai jos este o mostră din tabelul „Orders” („Comenzi”):
ProductID | OrderID | CustomerID | EmployeeID | OrderDate | ShipperID |
---|---|---|---|---|---|
1 | 10248 | 90 | 5 | 1996-07-04 | 3 |
2 | 10249 | 81 | 6 | 1996-07-05 | 1 |
3 | 10250 | 34 | 4 | 1996-07-08 | 2 |
4 | 10251 | 84 | 3 | 1996-07-08 | 1 |
5 | 10252 | 76 | 4 | 1996-07-09 | 2 |
Și selecția din tabelul „Employees” („Angajații”):
EmployeeID | LastName | FirstName | BirthDate | Photo | Notes |
---|---|---|---|---|---|
1 | Davolio | Nancy | 12/8/1968 | EmpID1.pic | Education includes a BA in psychology from Colorado State University. She also completed (The Art of the Cold Call). Nancy is a member of 'Toastmasters International'. |
2 | Fuller | Andrew | 2/19/1952 | EmpID2.pic | Andrew received his BTS commercial and a Ph.D. in international marketing from the University of Dallas. He is fluent in French and Italian and reads German. He joined the company as a sales representative, was promoted to sales manager and was then named vice president of sales. Andrew is a member of the Sales Management Roundtable, the Seattle Chamber of Commerce, and the Pacific Rim Importers Association. |
3 | Leverling | Janet | 8/30/1963 | EmpID3.pic | Janet has a BS degree in chemistry from Boston College). She has also completed a certificate program in food retailing management. Janet was hired as a sales associate and was promoted to sales representative. |
4 | Peacock | Margaret | 9/19/1958 | EmpID4.pic | Margaret holds a BA in English literature from Concordia College and an MA from the American Institute of Culinary Arts. She was temporarily assigned to the London office before returning to her permanent post in Seattle. |
5 | Buchanan | Steven | 3/4/1955 | EmpID5.pic | Steven Buchanan graduated from St. Andrews University, Scotland, with a BSC degree. Upon joining the company as a sales representative, he spent 6 months in an orientation program at the Seattle office and then returned to his permanent post in London, where he was promoted to sales manager. Mr. Buchanan has completed the courses 'Successful Telemarketing' and 'International Sales Management'. He is fluent in French. |
Următoarea instrucțiune SQL va returna toți angajații și toate comenzile pe care le-au plasat:
Run SQLSELECT Orders.OrderID, Employees.LastName, Employees.FirstName
FROM Orders
RIGHT JOIN Employees ON Orders.EmployeeID = Employees.EmployeeID
ORDER BY Orders.OrderID