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SQL ORDER BY


ORDER BY 關(guān)鍵字用于對結(jié)果集進(jìn)行排序。


SQL ORDER BY 關(guān)鍵字

ORDER BY 關(guān)鍵字用于對結(jié)果集按照一個(gè)列或者多個(gè)列進(jìn)行排序。

ORDER BY 關(guān)鍵字默認(rèn)按照升序?qū)τ涗涍M(jìn)行排序。如果需要按照降序?qū)τ涗涍M(jìn)行排序,您可以使用 DESC 關(guān)鍵字。

SQL ORDER BY 語法

SELECT column_name,column_name
FROM table_name
ORDER BY column_name,column_name ASC|DESC;

演示數(shù)據(jù)庫

在本教程中,我們將使用 JSON 樣本數(shù)據(jù)庫。

下面是選自 "Websites" 表的數(shù)據(jù):

+----+--------------+---------------------------+-------+---------+
| id | name         | url                       | alexa | country |
+----+--------------+---------------------------+-------+---------+
| 1  | Google       | https://www.google.cm/    | 1     | USA     |
| 2  | 淘寶          | https://www.taobao.com/   | 13    | CN      |
| 3  | 小白教程      | http://www.9t9t.com.cn    | 888  | CN      |
| 4  | 微博          | http://weibo.com/         | 20    | CN      |
| 5  | Facebook     | https://www.facebook.com/ | 3     | USA     |
+----+--------------+---------------------------+-------+---------+

ORDER BY 實(shí)例

下面的 SQL 語句從 "Websites" 表中選取所有網(wǎng)站,并按照 "alexa" 列排序:

實(shí)例

SELECT * FROM Websites ORDER BY alexa;

ORDER BY DESC 實(shí)例

下面的 SQL 語句從 "Websites" 表中選取所有網(wǎng)站,并按照 "alexa" 列降序排序:

實(shí)例

SELECT * FROM Websites ORDER BY alexa DESC;

ORDER BY 多列

下面的 SQL 語句從 "Websites" 表中選取所有網(wǎng)站,并按照 "country" 和 "alexa" 列排序:

實(shí)例

SELECT * FROM Websites ORDER BY country,alexa;