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-- RIGHT JOIN example (not supported in SQLite directly)
-- This query returns all enrollments and their corresponding student names,
-- with NULL for students not found.

-- View the students table
SELECT * FROM students;

-- View the enrollments table
SELECT * FROM enrollments;

SELECT students.name, enrollments.class_name
FROM students
RIGHT JOIN enrollments
ON students.student_id = enrollments.student_id;

# RIGHT JOIN

A `RIGHT JOIN` returns **all rows from the right table**, along with any matching rows from the left table.

If there's no match, the columns from the left table will contain `NULL`.

<br/>

## Syntax

Here is the syntax for a `RIGHT JOIN`:

```sql title="RIGHT JOIN Syntax"
SELECT columns
FROM table1
RIGHT JOIN table2
ON table1.column = table2.column;
```

* The *right table* (`table2`) comes after the RIGHT JOIN keyword
* All rows from the right table appear in the result, whether or not they have a match

<br/>

## Example: Students and Enrollments

Below is an example of a `RIGHT JOIN` between the `students` and `enrollments` tables.

*students*

| student_id | name          |
| ----------- | ------------- |
| 1           | John Smith    |
| 2           | Emily Davis   |
| 3           | Michael Brown |
| 4           | Jessica Lee   |
| 5           | David Johnson |

*enrollments*

| student_id | class_name |
| ----------- | ----------- |
| 1           | Math        |
| 2           | History     |
| 3           | Science     |
| 6           | Art         |
| 7           | Economics   |

```sql title="RIGHT JOIN example"
SELECT students.name, enrollments.class_name
FROM students
RIGHT JOIN enrollments
ON students.student_id = enrollments.student_id;
```

### Result:

| name          | class_name |
| ------------- | ----------- |
| John Smith    | Math        |
| Emily Davis   | History     |
| Michael Brown | Science     |
| NULL          | Art         |
| NULL          | Economics   |

>  The classes `Art` and `Economics` have no matching students, so their `name` values are `NULL`.

<br/>

## `LEFT JOIN` vs `RIGHT JOIN`

Both joins return unmatched rows, but from opposite sides:

- *LEFT JOIN* → keeps all rows from the left table, adds matches from the right  
- *RIGHT JOIN* → keeps all rows from the right table, adds matches from the left  

In essence, they are mirror images of each other.

> In practice,`LEFT JOIN` is used more frequently, and a `RIGHT JOIN` can usually be rewritten as a `LEFT JOIN` by swapping the table order.

A RIGHT JOIN in SQL returns all rows from the right table, regardless of whether there is a matching row in the left table. Unmatched rows from the right table will still appear, with NULL values for columns from the left table.

### What does a RIGHT JOIN return in SQL?

student_id	name
1	John Smith
2	Emily Davis
3	Michael Brown
4	Jessica Lee
5	David Johnson

name	class_name
John Smith	Math
Emily Davis	History
Michael Brown	Science
NULL	Art
NULL	Economics

RIGHT JOIN

Syntax

Example: Students and Enrollments

Result:

LEFT JOIN vs RIGHT JOIN

What does a RIGHT JOIN return in SQL?

`LEFT JOIN` vs `RIGHT JOIN`