

 从补丁 198 开始，Amazon Redshift 将不再支持创建新的 Python UDF。现有的 Python UDF 将继续正常运行至 2026 年 6 月 30 日。有关更多信息，请参阅[博客文章](https://aws.amazon.com/blogs/big-data/amazon-redshift-python-user-defined-functions-will-reach-end-of-support-after-june-30-2026/)。

# 使用 ORDER BY 的示例
<a name="r_Examples_with_ORDER_BY"></a>

返回 CATEGORY 表中的所有 11 行，这些行按第二列 CATGROUP 进行排序。对于具有相同 CATGROUP 值的结果，按字符串长度对 CATDESC 列值进行排序。然后，按列 CATID 和 CATNAME 排序。

```
select * from category order by 2, length(catdesc), 1, 3;

catid | catgroup |  catname  |                  catdesc
------+----------+-----------+----------------------------------------
10    | Concerts | Jazz      | All jazz singers and bands
9     | Concerts | Pop       | All rock and pop music concerts
11    | Concerts | Classical | All symphony, concerto, and choir conce
6     | Shows    | Musicals  | Musical theatre
7     | Shows    | Plays     | All non-musical theatre
8     | Shows    | Opera     | All opera and light opera
5     | Sports   | MLS       | Major League Soccer
1     | Sports   | MLB       | Major League Baseball
2     | Sports   | NHL       | National Hockey League
3     | Sports   | NFL       | National Football League
4     | Sports   | NBA       | National Basketball Association
(11 rows)
```

返回 SALES 表中的选定列（按最高的 QTYSOLD 值排序）。将结果限制为前 10 行：

```
select salesid, qtysold, pricepaid, commission, saletime from sales
order by qtysold, pricepaid, commission, salesid, saletime desc
limit 10;

salesid | qtysold | pricepaid | commission |      saletime
--------+---------+-----------+------------+---------------------
15401   |       8 |    272.00 |      40.80 | 2008-03-18 06:54:56
61683   |       8 |    296.00 |      44.40 | 2008-11-26 04:00:23
90528   |       8 |    328.00 |      49.20 | 2008-06-11 02:38:09
74549   |       8 |    336.00 |      50.40 | 2008-01-19 12:01:21
130232  |       8 |    352.00 |      52.80 | 2008-05-02 05:52:31
55243   |       8 |    384.00 |      57.60 | 2008-07-12 02:19:53
16004   |       8 |    440.00 |      66.00 | 2008-11-04 07:22:31
489     |       8 |    496.00 |      74.40 | 2008-08-03 05:48:55
4197    |       8 |    512.00 |      76.80 | 2008-03-23 11:35:33
16929   |       8 |    568.00 |      85.20 | 2008-12-19 02:59:33
(10 rows)
```

通过使用 LIMIT 0 语法返回列的列表，但不返回行：

```
select * from venue limit 0;
venueid | venuename | venuecity | venuestate | venueseats
---------+-----------+-----------+------------+------------
(0 rows)
```