ORDER BY 关键字用于对结果集进行排序。
SQL ORDER BY 关键字
ORDER BY 关键字用于对结果集按照一个列或者多个列进行排序。
ORDER BY 关键字默认按照升序对记录进行排序。如果需要按照降序对记录进行排序,您可以使用 DESC 关键字。
SQL ORDER BY 语法
SELECT column_name,column_name
FROM table_name
ORDER BY column_name,column_name ASC|DESC;
FROM table_name
ORDER BY column_name,column_name ASC|DESC;
演示数据库
在本教程中,我们将使用众所周知的 Northwind 样本数据库。
下面是选自 "Customers" 表的数据:
CustomerID | CustomerName | ContactName | Address | City | PostalCode | Country |
---|---|---|---|---|---|---|
1 | Alfreds Futterkiste | Maria Anders | Obere Str. 57 | Berlin | 12209 | Germany |
2 | Ana Trujillo Emparedados y helados | Ana Trujillo | Avda. de la Constitución 2222 | México D.F. | 05021 | Mexico |
3 | Antonio Moreno Taquería | Antonio Moreno | Mataderos 2312 | México D.F. | 05023 | Mexico |
4 | Around the Horn | Thomas Hardy | 120 Hanover Sq. | London | WA1 1DP | UK |
5 | Berglunds snabbköp | Christina Berglund | Berguvsvägen 8 | Luleå | S-958 22 | Sweden |
ORDER BY 实例
下面的 SQL 语句从 "Customers" 表中选取所有客户,并按照 "Country" 列排序:
实例
SELECT * FROM Customers
ORDER BY Country;
ORDER BY Country;
ORDER BY DESC 实例
下面的 SQL 语句从 "Customers" 表中选取所有客户,并按照 "Country" 列降序排序:
实例
SELECT * FROM Customers
ORDER BY Country DESC;
ORDER BY Country DESC;
ORDER BY Several Columns 实例
下面的 SQL 语句从 "Customers" 表中选取所有客户,并按照 "Country" 和 "CustomerName" 列排序:
实例
SELECT * FROM Customers
ORDER BY Country,CustomerName;
ORDER BY Country,CustomerName;