December 2019
Beginner
370 pages
8h 9m
English
book
Tableau Desktop Certified Associate: Exam Guide
by Dmitry Anoshin, JC Gillet, Fabian Peri, Radhika Biyani, Gleb Makarenko
Content preview from Tableau Desktop Certified Associate: Exam Guide
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Unions
A union is another way to combine your data. When you union two tables, you append the rows from one table to another. Since you are effectively stacking tables on top of each other, there is one important condition that must be satisfied – the data types of the columns that will be stacked need to be compatible. You should not stack a date column on top of a text column.
The following table includes a description of a union along with a Venn diagram visual to help you visualize how a union operates:
| Union | Description | Venn diagram of Union |
| Union | The result set of a union is all records from the first table appended to all records from the second table. |
To illustrate unions, we will append the Orders table to itself; this ...
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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.