SQL LEFT JOIN Keyword - W3Schools

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SQL LEFT JOIN

The LEFT JOIN returns all rows from the left table (table1), and only the matched rows from the right table (table2).

If there is no match in the right table, the result for the columns from the right table will be NULL.

The LEFT JOIN and LEFT OUTER JOIN keywords are equal - the OUTER keyword is optional.

SQL LEFT JOIN

LEFT JOIN Syntax

SELECT column_name(s) FROM table1 LEFT JOIN table2 ON table1.column_name = table2.column_name;

Demo Database

Below is a selection from the "Customers" table:

CustomerID CustomerName ContactName Address City PostalCode Country
1 Alfreds Futterkiste Maria Anders Obere Str. 57 Berlin 12209 Germany
2 Ana Trujillo Emparedados y helados Ana Trujillo Avda. de la Constitución 2222 México D.F. 05021 Mexico
3 Antonio Moreno Taquería Antonio Moreno Mataderos 2312 México D.F. 05023 Mexico

And a selection from the "Orders" table:

OrderID CustomerID EmployeeID OrderDate ShipperID
10308 2 7 1996-09-18 3
10309 37 3 1996-09-19 1
10310 77 8 1996-09-20 2

SQL LEFT JOIN Example

The following SQL returns all customers and their orders, including customers who have not placed any orders:

Example

SELECT Customers.CustomerName, Orders.OrderID FROM Customers LEFT JOIN Orders ON Customers.CustomerID = Orders.CustomerID ORDER BY Customers.CustomerName; Try it Yourself »

Tip: To find only the customers who have not placed any order, add a WHERE clause to filter for NULL values on the right table:

Example

SELECT Customers.CustomerName, Orders.OrderID FROM Customers LEFT JOIN Orders ON Customers.CustomerID = Orders.CustomerID WHERE Orders.CustomerID IS NULL; Try it Yourself » ❮ Previous Next ❯ ★ +1 Sign in to track progress

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