SQL LEFT JOIN

SQL LEFT JOIN clause is used to select all the matched records from the left side table, regardless if it has matched records in the right side table or not.

SQL LEFT JOIN Clause Syntax

SELECT Table1.Column1, Table1.Column2, ... , Table2.Column1, Table2.Column2, ...
FROM Table1
LEFT JOIN Table2
ON Table1.ColumnName = Table2.ColumnName

SQL LEFT JOIN Clause Example

Table: Employees

Table: Tickets

Select all the employees, if they have any tickets, list the tickets:

SELECT Employees.EmployeeId
           , Employees.FirstName
           , Employees.LastName
           , Tickets.TicketNo
FROM Employees
LEFT JOIN Tickets
ON Employees.EmployeeId = Tickets.EmployeeId

The result will look like:

Note: The employee whose EmployeeId is 206 doesn’t have any records matched in the table Tickets, but he is still listed in the result with the TicketNo null.