14. 练习:LIMIT
你会使用 LIMIT 吗?
-
编写一个查询,将响应限制在前 15 行,和包括
web_events
表中的
occurred_at
、account_id
和channel
字段,我们来试一下。
Workspace
This section contains either a workspace (it can be a Jupyter Notebook workspace or an online code editor work space, etc.) and it cannot be automatically downloaded to be generated here. Please access the classroom with your account and manually download the workspace to your local machine. Note that for some courses, Udacity upload the workspace files onto https://github.com/udacity , so you may be able to download them there.
Workspace Information:
- Default file path:
- Workspace type: sql-evaluator
- Opened files (when workspace is loaded): n/a
讲师注释
为了保留我的 SQL 注释,我个人使用
Atom
文本编辑器。 我用
.sql
扩展名保存文件,以便语法得以高亮显示,不过你也可以使用其他方式保留自己的注释。 使用 Notepad,Word 或任何其他你喜欢的软件皆可。 如下是我的文件在 Atom 中显示的样式。
![](img/screen-shot-2017-08-02-at-10.48.24-pm.png)