![]() If the value in the column salesRepEmployeeNumber is NULL, which means the customer does not have any sales representative. And each customer is taken care of by zero or one sales representative. The column salesRepEmployeeNumber in the table customers links to the column employeeNumber in the employees table.Ī sales representative, or an employee, may be in charge of zero or more customers. We’ll use the tables employees and customers from the sample database for the demonstration: Therefore, you can use them interchangeably. Notice that the RIGHT OUTER JOIN is a synonym for RIGHT JOIN. It’s important to emphasize that RIGHT JOIN and LEFT JOIN clauses are functionally equivalent, and they can replace each other as long as the table order is reversed. In other words, the RIGHT JOIN returns all rows from the right table regardless of having matching rows from the left table or not. If a row from the right table does not have a matching row from the left table, the RIGHT JOIN combines columns of rows from the right table with NULL values for all columns of the right table into a new row and includes this row in the result set. If both rows cause the join condition to evaluate to TRUE, the RIGHT JOIN combines columns of these rows into a new row and includes this new row in the result set. It matches each row from the right table with every row from the left table. The RIGHT JOIN starts selecting data from the right table ( t2). Therefore, the following join conditions are equivalent: ON t1.column_name = t2.column_name Code language: SQL (Structured Query Language) ( sql )Īnd USING (column_name) Code language: SQL (Structured Query Language) ( sql ) RIGHT JOIN t2 USING(column_name) Code language: SQL (Structured Query Language) ( sql ) If the join_condition uses the equal operator ( =) and the joined columns of both tables have the same name, and you can use the USING syntax like this: SELECT The join_condition specifies the rule for matching rows from both tables.The t1 is the left table and t2 is the right table.Join_condition Code language: SQL (Structured Query Language) ( sql ) Here’s the syntax of the RIGHT JOIN of two tables t1 and t2: SELECT MySQL RIGHT JOIN is similar to LEFT JOIN, except that the treatment of the joined tables is reversed. Summary: in this tutorial, you will learn how to use the MySQL RIGHT JOIN to query data from two tables. ![]()
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