按一列排序
mysql> select prod_name
-> from products
-> order by prod_name;
+---------------------+
| prod_name |
+---------------------+
| 12 inch teddy bear |
| 18 inch teddy bear |
| 8 inch teddy bear |
| Bird bean bag toy |
| Fish bean bag toy |
| King doll |
| Queen doll |
| Rabbit bean bag toy |
| Raggedy Ann |
+---------------------+
9 rows in set (0.00 sec)
按多列排序
mysql> select prod_id, prod_price, prod_name
-> from products
-> order by prod_price, prod_name;
+---------+------------+---------------------+
| prod_id | prod_price | prod_name |
+---------+------------+---------------------+
| BNBG02 | 3.49 | Bird bean bag toy |
| BNBG01 | 3.49 | Fish bean bag toy |
| BNBG03 | 3.49 | Rabbit bean bag toy |
| RGAN01 | 4.99 | Raggedy Ann |
| BR01 | 5.99 | 8 inch teddy bear |
| BR02 | 8.99 | 12 inch teddy bear |
| RYL01 | 9.49 | King doll |
| RYL02 | 9.49 | Queen doll |
| BR03 | 11.99 | 18 inch teddy bear |
+---------+------------+---------------------+
9 rows in set (0.00 sec)
指定排序方向:desc
mysql> select prod_id, prod_price, prod_name
-> from products
-> order by prod_price desc;
+---------+------------+---------------------+
| prod_id | prod_price | prod_name |
+---------+------------+---------------------+
| BR03 | 11.99 | 18 inch teddy bear |
| RYL01 | 9.49 | King doll |
| RYL02 | 9.49 | Queen doll |
| BR02 | 8.99 | 12 inch teddy bear |
| BR01 | 5.99 | 8 inch teddy bear |
| RGAN01 | 4.99 | Raggedy Ann |
| BNBG01 | 3.49 | Fish bean bag toy |
| BNBG02 | 3.49 | Bird bean bag toy |
| BNBG03 | 3.49 | Rabbit bean bag toy |
+---------+------------+---------------------+
9 rows in set (0.00 sec)
mysql> select prod_id, prod_price, prod_name
-> from products
-> order by prod_price desc, prod_name;
+---------+------------+---------------------+
| prod_id | prod_price | prod_name |
+---------+------------+---------------------+
| BR03 | 11.99 | 18 inch teddy bear |
| RYL01 | 9.49 | King doll |
| RYL02 | 9.49 | Queen doll |
| BR02 | 8.99 | 12 inch teddy bear |
| BR01 | 5.99 | 8 inch teddy bear |
| RGAN01 | 4.99 | Raggedy Ann |
| BNBG02 | 3.49 | Bird bean bag toy |
| BNBG01 | 3.49 | Fish bean bag toy |
| BNBG03 | 3.49 | Rabbit bean bag toy |
+---------+------------+---------------------+
9 rows in set (0.00 sec)
可見desc只作用於其前面的1列,而之前的distinct會作用於其後的所有列
limit和order by組合
選出最大值
mysql> select prod_price
-> from products
-> order by prod_price desc
-> limit 1;
+------------+
| prod_price |
+------------+
| 11.99 |
+------------+
1 row in set (0.00 sec)
返回最大的前4個
mysql> select prod_price
-> from products
-> order by prod_price desc
-> limit 4;
+------------+
| prod_price |
+------------+
| 11.99 |
| 9.49 |
| 9.49 |
| 8.99 |
+------------+
總結
- order by子句必須在from子句後面;limit子句必須在order by子句後面