sql order by 语句的使用方法

ORDER BY 语句用于根据指定的列对结果集进行排序。

ORDER BY 语句默认按照升序对记录进行排序。

如果您希望按照降序对记录进行排序，可以使用 DESC 关键字。

实例

SELECT Company, OrderNumber FROM Orders ORDER BY Company, OrderNumber

注意：在以上的结果中有两个相等的公司名称 (www.111cn.net)。只有这一次，在第一列中有相同的值时，第二列是以升序排列的。如果第一列中有些值为 nulls 时，情况也是这样的。

实例

mysql教程> CREATE TABLE Employee(
    ->     id            int,
    ->     first_name    VARCHAR(15),
    ->     last_name     VARCHAR(15),
    ->     start_date    DATE,
    ->     end_date      DATE,
    ->     salary        FLOAT(8,2),
    ->     city          VARCHAR(10),
    ->     description   VARCHAR(15)
    -> );
Query OK, 0 rows affected (0.03 sec)

mysql>
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->              values (1,'Jason',    'Martin', '19960725', '20060725', 1234.56, 'Toronto', 'Programmer');
Query OK, 1 row affected (0.02 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(2,'Alison',   'Mathews', '19760321', '19860221', 6661.78, 'Vancouver','Tester');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(3,'James',    'Smith',    '19781212', '19900315', 6544.78, 'Vancouver','Tester');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(4,'Celia',    'Rice',     '19821024', '19990421', 2344.78, 'Vancouver','Manager');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(5,'Robert',   'Black',    '19840115', '19980808', 2334.78, 'Vancouver','Tester');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(6,'Linda',    'Green',    '19870730', '19960104', 4322.78,'New York', 'Tester');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(7,'David',    'Larry',    '19901231', '19980212', 7897.78,'New York', 'Manager');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(8,'James',    'Cat',     '19960917', '20020415', 1232.78,'Vancouver', 'Tester');
Query OK, 1 row affected (0.02 sec)

mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id   | first_name | last_name | start_date | end_date   | salary | city      | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
|    1 | Jason      | Martin    | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto   | Programmer |
|    2 | Alison     | Mathews   | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester      |
|    3 | James      | Smith     | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester      |
|    4 | Celia      | Rice      | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager     |
|    5 | Robert     | Black     | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester      |
|    6 | Linda      | Green     | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester      |
|    7 | David      | Larry     | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager     |
|    8 | James      | Cat       | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester      |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.00 sec)

mysql>
mysql>
mysql>
mysql>
mysql> SELECT * FROM employee ORDER BY city;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id   | first_name | last_name | start_date | end_date   | salary | city      | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
|    6 | Linda      | Green     | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester      |
|    7 | David      | Larry     | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager     |
|    1 | Jason      | Martin    | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto   | Programmer |
|    2 | Alison     | Mathews   | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester      |
|    3 | James      | Smith     | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester      |
|    4 | Celia      | Rice      | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager     |
|    5 | Robert     | Black     | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester      |
|    8 | James      | Cat       | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester      |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.02 sec)

order by还可以对日期进行排序，
实例

mysql>
mysql>
mysql> CREATE TABLE Employee(
    ->     id            int,
    ->     first_name    VARCHAR(15),
    ->     last_name     VARCHAR(15),
    ->     start_date    DATE,
    ->     end_date      DATE,
    ->     salary        FLOAT(8,2),
    ->     city          VARCHAR(10),
    ->     description   VARCHAR(15)
    -> );
Query OK, 0 rows affected (0.03 sec)

mysql>
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->              values (1,'Jason',    'Martin', '19960725', '20060725', 1234.56, 'Toronto', 'Programmer');
Query OK, 1 row affected (0.02 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(2,'Alison',   'Mathews', '19760321', '19860221', 6661.78, 'Vancouver','Tester');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(3,'James',    'Smith',    '19781212', '19900315', 6544.78, 'Vancouver','Tester');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(4,'Celia',    'Rice',     '19821024', '19990421', 2344.78, 'Vancouver','Manager');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(5,'Robert',   'Black',    '19840115', '19980808', 2334.78, 'Vancouver','Tester');
Query OK, 1 row affected (0.01 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(6,'Linda',    'Green',    '19870730', '19960104', 4322.78,'New York', 'Tester');
Query OK, 1 row affected (0.02 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(7,'David',    'Larry',    '19901231', '19980212', 7897.78,'New York', 'Manager');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary, City,       Description)
    ->               values(8,'James',    'Cat',     '19960917', '20020415', 1232.78,'Vancouver', 'Tester');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id   | first_name | last_name | start_date | end_date   | salary | city      | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
|    1 | Jason      | Martin    | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto   | Programmer |
|    2 | Alison     | Mathews   | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester      |
|    3 | James      | Smith     | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester      |
|    4 | Celia      | Rice      | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager     |
|    5 | Robert     | Black     | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester      |
|    6 | Linda      | Green     | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester      |
|    7 | David      | Larry     | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager     |
|    8 | James      | Cat       | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester      |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.00 sec)

mysql>
mysql>
mysql>
mysql>
mysql> SELECT first_name, start_date FROM employee ORDER BY start_date;
+------------+------------+
| first_name | start_date |
+------------+------------+
| Alison     | 1976-03-21 |
| James      | 1978-12-12 |
| Celia      | 1982-10-24 |
| Robert     | 1984-01-15 |
| Linda      | 1987-07-30 |
| David      | 1990-12-31 |
| Jason      | 1996-07-25 |
| James      | 1996-09-17 |
+------------+------------+
8 rows in set (0.00 sec)

这样在我们数据库教程中以date形式存放数据也可以方便快捷进行排序操作了。

时间： 2024-08-31 17:50:07

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