August 2022
Beginner to intermediate
463 pages
9h 22m
Chinese
Content preview from Tableau Prep即学即用
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.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.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.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.
74
第
9
章
处理字符串数据
当我考虑数据准备任务的时候，我立刻就会想到需要处理包含字符串数据的字段。
客户名称、产品描述、消息和地理名称都是在准备数据分析时可能需要操作的字符
串。本章将介绍什么是字符串以及它与数字的区别。有了这些背景知识，就可以通
过计算和
Prep Builder
的内置函数进一步探索如何使用字符串数据字段。
9.1
字符串意味着什么
谈到数据，大多数人想到的是我们正在进行求和、求平均或寻找最小和最大值的操
作。但是，在我们开始分析不同层次的东西之前，这些运算操作并不能告诉我们太
多信息。例如，地区的平均销售额或每个公司的总销售额。
字符串通常是我们在
Tableau Desktop
等工具中对数据进行分类的那些维度。
Tableau
用
Abc
图标来表示字符串（见图
9-1
）。
字符串数据字段在它们可以容纳的值方面是最灵活的。通常情况下，它们可以包含
从
A
到
Z
和
0
到
9
的所有内容，以及标点符号和大多数其他字符。但是，这种灵活
性也带来了麻烦，因为各种不同的值会让你在准备数据时感到头疼。
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
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.