August 2022
Beginner to intermediate
463 pages
9h 22m
Chinese
Content preview from Tableau Prep即学即用
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152
｜
第
17
章
图
17
-
11
：将球队名称从表名中拆分出来
17.3.3
公司合并
随着云端软件的兴起，越来越多的公司开始使用类似的工具和数据结构。这意味着，
当部门和组织合并时，他们可以将各自产生的数据联合起来。例如，将两家都使用
Salesforce
云服务的公司合并时，使用联合来整合合并后的销售渠道列表将非常简单。
17.4
多表和通配符联合
在数据联合操作的部分流程中，可以将两个以上的输入数据添加到一个联合中。但
是，如果有多个输入数据源要联合，那么为每个数据源逐个地添加来源信息，这种
｜
153
联合数据
操作可能会很容易令人觉得乏味。与之不同，在
Prep Builder
的添加输入信息的步
骤中，可以选择
Wildcard union
（通配符联合），而不是
Single table
（单表）操作。
通配符有三个部分，可以选择与指定的模式相匹配的任何文件夹（包括子文件夹）、
文件或工作表（见图
17-12
）。
图
17
-
12
：在输入步骤上设置通配符联合
在如图
17-12
所示的界面中，可以看到
Matching Pattern
（匹配模式）旁边有一个星
号（
*
）。星号在数据相关领域中作为通配符使用，起到了过滤的作用，从而能够更
好地控制联合数据中应该、不应该提取的内容。
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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.
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.