freeCodeCamp/guide/chinese/sql/sql-order-by-keyword/index.md

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SQL Order By Keyword SQL按顺序排序

SQL按顺序排序

订购方式ASCDESC

ORDER BY为我们提供了一种方法可以通过SELECT部分中的一个或多个项来对结果集进行排序。这是一个按FullName降序排列学生的SQL。默认排序顺序是升序ASC但要按相反顺序降序排序请使用DESC。

SELECT studentID, FullName, sat_score 
 FROM student 
 ORDER BY FullName DESC; 
+-----------+------------------------+-----------+ 
 | studentID | FullName               | sat_score | 
 +-----------+------------------------+-----------+ 
 |         2 | Teri Gutierrez         |       800 | 
 |         3 | Spencer Pautier        |      1000 | 
 |         6 | Sophie Freeman         |      1200 | 
 |         9 | Raymond F. Boyce       |      2400 | 
 |         1 | Monique Davis          |       400 | 
 |         4 | Louis Ramsey           |      1200 | 
 |         7 | Edgar Frank "Ted" Codd |      2400 | 
 |         8 | Donald D. Chamberlin   |      2400 | 
 |         5 | Alvin Greene           |      1200 | 
 +-----------+------------------------+-----------+ 
 9 rows in set (0.00 sec) 

这是与上述相比较的UN-ORDERED当前完整学生列表。

SELECT studentID, FullName, sat_score, rcd_updated FROM student; 
+-----------+------------------------+-----------+---------------------+ 
 | studentID | FullName               | sat_score | rcd_updated         | 
 +-----------+------------------------+-----------+---------------------+ 
 |         1 | Monique Davis          |       400 | 2017-08-16 15:34:50 | 
 |         2 | Teri Gutierrez         |       800 | 2017-08-16 15:34:50 | 
 |         3 | Spencer Pautier        |      1000 | 2017-08-16 15:34:50 | 
 |         4 | Louis Ramsey           |      1200 | 2017-08-16 15:34:50 | 
 |         5 | Alvin Greene           |      1200 | 2017-08-16 15:34:50 | 
 |         6 | Sophie Freeman         |      1200 | 2017-08-16 15:34:50 | 
 |         7 | Edgar Frank "Ted" Codd |      2400 | 2017-08-16 15:35:33 | 
 |         8 | Donald D. Chamberlin   |      2400 | 2017-08-16 15:35:33 | 
 |         9 | Raymond F. Boyce       |      2400 | 2017-08-16 15:35:33 | 
 +-----------+------------------------+-----------+---------------------+ 
 9 rows in set (0.00 sec) 

与所有这些SQL事物一样它们比本入门指南中的内容更多。

我希望这至少足以让你开始。

请参阅您的数据库管理员手册,并自己尝试不同的选项。