# `OUTER JOIN` and `NULL`
+ **`NULL`** behavior in **`OUTER JOIN`**:
__*NULL Behavior*__
```
tidb> SELECT a.name, d.name FROM test.a a RIGHT JOIN test.d d ON a.id=d.id;
+------+------+
| name | name |
+------+------+
| AA   | DA   |
| AB   | DB   |
| NULL | DC   |
| NULL | NULL |
+------+------+

tidb> SELECT a.name, d.name, a.id, d.id FROM test.a a RIGHT JOIN test.d d ON a.id=d.id;
+------+------+------+------+
| name | name | id   | id   |
+------+------+------+------+
| AA   | DA   |    1 |    1 |
| AB   | DB   |    2 |    2 |
| NULL | DC   | NULL | NULL |
| NULL | NULL | NULL |    ~!@5@!~ |
+------+------+------+------+
```

------------------------------------------------------------
