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.
47
第
5
章
连接文件中的数据
5.1
基于文件之上的文件
在任何数据准备、数据可视化或数据分析项目中，要做的第一步都是输入数据。通
过本章内容，能掌握如何以及为什么要将数据文件连接到
Prep Builder
，在哪里可以
找到这些文件，以及数据文件在准备数据过程中可能带来的挑战。数据可以有许多
不同的形式，但在
Prep Builder
中最常见的输入文件格式是
Excel
、
CSV
或纯文本文
件（见图
5-1
）。
图
5
-
1
：软件生成的系统文件
48
｜
第
5
章
5.1.1
电子表格
对许多人来说，第一次处理数据的经验涉及一个无处不在的软件——
Microsoft
Excel
。电子表格已经成为数据存储、操作和基本报告的万能工具。世界上每个组织
的所有计算机上都保存着几十个甚至上百个电子表格。它们都包含了有用的信息、
原始数据或参考表格，可以帮助回答组织关注的问题。
然而，当涉及数据准备和数据分析时，电子表格面临一些潜在的问题（其中一些不
是电子表格所特有的）：
准确性
添加到电子表格后，数据可能会发生变化。
时效性
数据在添加后可能已经过时。
优化问题
所有操作或分析通常都是手动和不可重复的。
规模问题
随着行和列的限制，有时数据的增长超过了电子表格的处理能力。
共享问题
多人使用多个表格会造成混乱和错误。
单点问题
计算和分析仅限于进行计算和分析的单一工作簿。 ...
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.