SQL: ORDER BY Clause

 

SQL: ORDER BY Clause

The ORDER BY clause allows you to sort the records in your result set. The ORDER BY clause can only be used in SELECT statements.

译： ORDER BY 允许你在结果集中对记录进行排序。 ORDER BY 只能够用于 SELECT 语句。

The syntax for the ORDER BY clause is:

译： ORDER BY 的语法如下：

SELECT columns
FROM tables
WHERE predicates
ORDER BY column ASC/DESC;

The ORDER BY clause sorts the result set based on the columns specified. If the ASC or DESC value is omitted, the system assumed ascending order.

译： ORDER BY 是根据指定的列进行排序。如果省略 ASC 或者 DESC ，系统默认为升序。

ASC indicates ascending order. (default)
DESC indicates descending order.

译： ASC 表明升序（默认）
DESC 表明降序。

 

Example #1

SELECT supplier_city
FROM supplier
WHERE supplier_name = 'IBM'
ORDER BY supplier_city;

This would return all records sorted by the supplier_city field in ascending order.

译：结果将会以 supplier_city 排序的升序结果返回所有记录。

Example #2

SELECT supplier_city
FROM supplier
WHERE supplier_name = 'IBM'
ORDER BY supplier_city DESC;

This would return all records sorted by the supplier_city field in descending order.

译：以 supplier_city 的降序结果返回所有记录。

Example #3

You can also sort by relative position in the result set, where the first field in the result set is 1. The next field is 2, and so on.

译：你可以采用字段的相对位置作为排序，第一个字段为 1 ，下一个为 2 等等。

SELECT supplier_city
FROM supplier
WHERE supplier_name = 'IBM'
ORDER BY 1 DESC;

This would return all records sorted by the supplier_city field in descending order, since the supplier_city field is in position #1 in the result set.

译：这样会以 supplier_city 的降序返回所有结果，因为 supplier_city 在结果集中的位置是 #1 。

Example #4

SELECT supplier_city, supplier_state
FROM supplier
WHERE supplier_name = 'IBM'
ORDER BY supplier_city DESC, supplier_state ASC;

This would return all records sorted by the supplier_city field in descending order, with a secondary sort by supplier_state in ascending order.

译：返回以 supplier_city 为降序、 supplier_state 为二级升序的结果。