August 2022
Beginner to intermediate
463 pages
9h 22m
Chinese
Content preview from Tableau Prep即学即用
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280
｜
第
31
章
所得数据集如图
31-7
所示。
图
31
-
7
：从 REGEX_REPLACE() 示例中得到的数据集
31.5
常用的正则表达式命令
为了能够使用正则表达式函数，需要使用正则命令指定正在寻找的模式。在正则表
达式中，大小写敏感性取决于
Prep Builder
所连接的数据源，因此在输入字符串名
称时需要小心。表
31-1
列出了你将使用的关键正则命令。
表
31
-
1
：常用的正则表达式命令
\d
任意
0
～
9
的数字
\d+
一个或多个数字
\a
～
z
任意小写字母
\A
～
Z
任意大写字母
\D
任何非数字
\s Whitespace
，
空白符
，
如
tab
、
backspace
、
制表符
、
换行符等
\w
任意单次的字符
^
字符串的开始
$
字符串的结束
( )
提取括号内的任何内容
，
如同
REGEXP_EXTRACT()
函数
{ }
明确指定子串中的一个数字
，
通过在括号中添加一个数字来设置
（
例如
，
{3}
）
要想测试正则表达式，你可以使用
Tableau Prep
或在为测试正则表达式而建立的网
站上获得实时反馈信息（例如，
http://regex101.com
）。
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.