August 2022
Beginner to intermediate
463 pages
9h 22m
Chinese
Content preview from Tableau Prep即学即用
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数据准备规划
｜
29
图
3
-
2
：数据集草图，突出了类别和价值
通过识别分类数据和囊括分析所需字段的值，可以看到数据集的完整性，为什么说
目前还没有准备好进行分析，以及准备数据可能需要做什么。注意，关注所有的细
节数据并不是至关重要的。事实上，简化草图可以帮助你专注于核心问题，而不是
淹没在细节信息中。
3.2
阶段
2
：明确目标状态
那么，想要的数据目标状态是什么呢？
对于大多数现代数据分析工具或可视化软件，需要将数据结构化为列。第一行包含
列标题——数据的标签，随后的每一行应该是一个单独的记录或实例。例如，每一
行可以代表从商店购买的产品或每月的新员工数量（见图
3-3
）。
图
3
-
3
：分析数据集的期望状态示例
30
｜
第
3
章
了解数据的每一行代表什么，是正确准备和分析数据的关键。大多数工具都需要一
个单一的输入表，所以分析过程中所需的所有数据字段都应该放在一个表中。
绘制数据集草图
简单的数据集可以很容易地勾勒出来。不过，绘制有很多列的宽数据集，可能
是一个更庞大的任务。首先列出分类数据，也就是把数据细分为几组。比起数
值的范围无限特性，通常来说，类别的数量是有限的。所以对数据进行分类，
通过描述数据集中的数值，这样做是有意义的。这些类别是后续分析数字时所
用的参数，如
Region
（地区）、
Customer
（客户）
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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.