MySQLでソートをした際のNULLの位置について
table
| id | name |
|---|---|
| 1 | aaa |
| 2 | NULL |
| 3 | bbb |
昇順(NULLが上)
SELECT * FROM table ORDER BY name ASC;
実行結果:
| id | name |
|---|---|
| 2 | NULL |
| 1 | aaa |
| 3 | bbb |
降順(NULLが下)
SELECT * FROM table ORDER BY name DESC;
実行結果:
| id | name |
|---|---|
| 3 | bbb |
| 1 | aaa |
| 2 | NULL |
昇順(NULLが下)
SELECT * FROM table ORDER BY name IS NULL ASC;
実行結果:
| id | name |
|---|---|
| 1 | aaa |
| 3 | bbb |
| 2 | NULL |
降順(NULLが上)
SELECT * FROM table ORDER BY name IS NULL DESC;
実行結果:
| id | name |
|---|---|
| 2 | NULL |
| 3 | bbb |
| 1 | aaa |