August 2022
Beginner to intermediate
463 pages
9h 22m
Chinese
Content preview from Tableau Prep即学即用
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134
第
16
章
将数据集连接到一起
无论你的数据是来自文件、数据库，还是两者兼而有之，都需要掌握
join
（连接）操作，
因为大多数软件都需要一个大的数据表来参考分析。你的数据集将来自很多不同的
源，所以能够将它们结合起来是关键。这将允许你从每个数据源中获取数据列，并
在输出中相互结合起来使用。它们所包含的数据行将被添加到生成的数据集中。
本章中的大多数示例将使用
Preppin
’
Data 2019
：第
29
周挑战赛（
https://oreil.ly/-
Dk2g
）的输入数据集。我们将介绍使用
join
（连接）操作的逻辑和术语，如何在
Prep Builder
中将数据集连接在一起，以及在不同情况下使用哪种类型的连接。
16.1
如何在
Prep Builder
中连接数据集
在
Prep Builder
中，连接不同的数据源非常容易。只需将一个数据源拖向另一个数
据源，
Prep Builder
就会给你一些选项（见图
16-1
）。
图
16
-
1
：将一个步骤拖向另一个会触发 Join/Union（连接 / 联合）选项
｜
135
将数据集连接到一起
通过拖动第二个数据集（在本例中为
Subscription Pricing
，订阅定价）到原始（蓝色）
数据流（清理
2
），会出现
Union
（联合）或
Join
（连接）数据集的选项。
如果将鼠标悬停在 ...
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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.