August 2022
Beginner to intermediate
463 pages
9h 22m
Chinese
Content preview from Tableau Prep即学即用
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351
第
39
章
支撑你的数据
Scaffolding
（支撑）这个名词你可能不常遇到，但它所解决的困难问题却越来越多
地出现在现代数据处理中。
39.1
什么是支撑
支撑是指在数据集中填充缺失的数据行，以协助分析的过程。一个数据集可能看起
来是完整的──没有
null
（空值），每个实体都有一条记录──但仍然不适合于你
希望进行的分析。考虑一个移动电话运营商，其希望分析来自签约客户的月收入。
图
39-1
展示了该运营商可能拥有的数据。
图
39
-
1
：需要 Scaffolding（支撑）来协助分析的数据集
如你所见，运营商有客户的记录、合同开始日期、合同长度，以及服务的月价格。但是，
没有日期来确定我们所要分析的价值──月收入。唯一用于分析的日期是合同开始
352
｜
第
39
章
日期和结束日期。如果合同为期两年，我们需要
24
条记录才能获得完整的数据洞察
力。如图
39-2
所示，每个
Customer ID
（客户
ID
）只有一个月的收入，我们无法看
到随着时间的推移而获得的收入。
图
39
-
2
：图
39
-
1
中数据集的可视化结果
Scaffolding
（支撑）是解决这个问题的答案。该技术为分析所需的每一条“缺失”
记录增加一行。在移动电话运营商的例子中，支撑将创建额外的行，使每个月的付
款有自己的记录。由此产生的数据集将为每个合同、每个月的服务成本提供一条记 ...
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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.
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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.