Description
SQL RIGHT JOIN can be used to join two tables, which returns all the rows from the right table along with the associated data from the left table that met the join condition.
If there is a row in the right table but no match found in the left table, then the associate result row contains NULL values against all the columns coming from the left table.
The left table is the one that appears leftmost in the JOIN clause, and the right table is the one that appears rightmost.
- It is a type of outer join, so it is also referred to as the left outer join.
- It can be implemented on SELECT, UPDATE, and DELETE statements.
Also, check the other types of outer join - left join and full join.
Syntax
Here is the basic syntax of a SELECT statement with a RIGHT JOIN.
- The
table1
andtable2
represents the left and right table names. - The
column_list
represents the column names from either or both the tables. - The
column1
andcolumn2
are the columns from the left and right tables, which are used for creating the LEFT JOIN.
SELECT column_list
FROM table1
RIGHT JOIN table2 ON table1.column1 = table2.column2;
Table Data
Consider the below data in the orders, customers, and shippers tables, with the below observations.
- Tables orders and customers are relationally connected via
customer_id
column. - Tables orders and shippers are relationally connected via
shipper_id
column.
Orders Table Data
order_id | order_date | order_value | customer_id | shipper_id |
10250 | 2014-07-05 | 1807.5 | 3 | 1 |
10251 | 2014-07-15 | 1159 | 2 | 2 |
10252 | 2014-07-18 | 2822 | 1 | 3 |
10253 | 2014-07-19 | 2575.3 | 3 | 2 |
10254 | 2014-07-24 | 1256.25 | 1 | 3 |
10255 | 2014-07-31 | 9247.5 | 5 | 1 |
Customers Table Data
customer_id | customer_name | address | city | country | postal_code |
1 | Maria Anders | Obere Str. 57 | Berlin | Germany | 12209 |
2 | Fran Wilson | C/ Araquil, 67 | Madrid | Spain | 28023 |
3 | Dominique Perrier | 25, rue Lauriston | Paris | France | 75016 |
4 | Martin Blank | Via Monte Bianco 34 | Turin | Italy | 10100 |
Shipper Table Data
shipper_id | shipper_name | phone |
1 | Speedy Express | (503) 555-9831 |
2 | United Package | (503) 555-3199 |
3 | Federal Shipping | (503) 555-9931 |
Right Join Multiple Columns
The below SQL statement fetches data from both tables by joining them together as mentioned below.
- Returns all the rows from the right table along with the matching data from the left table, based on the join.
- For a right table row, if the associated left table row is not found, then the resulted row contains NULL values against all the columns coming from the left table.
- For a right table row, if there is more than one matching row on the left table, then the resulted row contains includes the values from the first matching row against all the columns coming from the left table.
SELECT order_id, order_date, order_value, customer_name
FROM orders
RIGHT JOIN customers ON orders.customer_id = customers.customer_id;
After successful execution, the output contains all rows from the left table along with the required data from the right table, as shown below.
- For the last right table row, there is no matching record on the left table, so all left table columns are NULL for that specific record.
order_id | order_date | order_value | customer_name |
10252 | 2014-07-18 | 2822 | Maria Anders |
10251 | 2014-07-15 | 1159 | Fran Wilson |
10250 | 2014-07-05 | 1807.5 | 3 |
NULL | NULL | NULL | Martin Blank |
Right Join All Columns
The below SQL statement fetches data from both the tables as mentioned below.
- The
SELECT *
returns all the columns from both the tables, without repeating the joined columns.
SELECT *
FROM orders
RIGHT JOIN customers ON orders.customer_id = customers.customer_id;
After successful execution, the output contains data from both the joined tables as shown below.
- For the last right table row, there is no matching record on the left table, so all left table columns are NULL for that specific record.
order_id | order_date | order_value | supplier_id | customer_id | customer_name | address | city | country | postal_code |
10252 | 2014-07-18 | 2822 | 3 | 1 | Maria Anders | Obere Str. 57 | Berlin | Germany | 12209 |
10251 | 2014-07-15 | 1159 | 2 | 2 | Fran Wilson | C/ Araquil, 67 | Madrid | Spain | 28023 |
10250 | 2014-07-05 | 1807.5 | 1 | 3 | Dominique Perrier | 25, rue Lauriston | Paris | France | 75016 |
NULL | NULL | NULL | NULL | 4 | Martin Blank | Via Monte Bianco 34 | Turin | Italy | 10100 |
Tips & Recommendations
An outer join is a join that includes rows in the result set even though there may not be a match between the rows of the joined tables.
In a join query, the left table is the one that appears leftmost in the JOIN clause, and the right table is the one that appears rightmost.
In an outer join, wherever the database system can't find a match record, it places NULL values to indicate that the data do not exist in columns of such table.
Overall
We now know how can we use a SELECT Statement with RIGHT JOIN to combine tables and fetch data from the joined tables.