Introduction
Part I: Getting Started
Before we can visualize data, we must understand that data. This book introduces the idea of looking at data in new ways, focusing on data quality and consistency. Specifically, we look at:
- The layout and important parts of the Tableau Data Prep tool (Chapter 1)
- Connecting to data (Chapter 2) - Data quality and consistency (Chapters 3,4,5)
- The shape of the data. Is the data oriented on columns or rows? How to decide. Why it matters. (Chapter 6)
- What is the level of detail in the source data? Why is that important?(Chapter 7)
- Combining source data to bring in more fields (Chapter 8) and rows (Chapter 9)
- Saving the data flow and the results of our data prep work (Chapter 10 and 11)
- Common cleanup and setup tasks in Tableau Desktop (Chapters 12-15)
We will start the book with the end in mind, telling a story of connecting to data, cleaning that data, creating a dashboard to display insights from the data with Tableau Desktop and sharing those insights in Tableau Server.
Chapter 1: Getting to Know the Tableau Data Prep Tool
An introduction to the Tableau Data Prep tool environment with focus on key tools and menu options. A description of the source data that will be used for all demo in this book and links to where that data can be downloaded.
Part II: Connecting To Data
Chapter 2: The Input Step: Connecting to Data
A tour of the input step with discussion of the types of data that can be brought into to a data flow including examples of a simple data flow with one input and a complex data flow with multiple inputs.
Chapter 3: The Cleaning Step: The Heavy Lifting Happens Here
Cleaning is one of the most important phases of data prep. In this section we look at.
- Renaming fields
- Changing data types
- Splitting fields that contain multiple values into individual fields with one value in each field
- Combining multiple fields into one field
- Adding new fields that contain the results of calculations
- Removing spaces, numbers or any unwanted characters from a field value
Chapter 4: The Group and Replace Step: It's Like a Magic Wand for Inconsistent Data
Tableau has some very impressive grouping and replacing functionality built in to the Data Prep tool. In this chapter we will look at scenarios that discuss misspellings and common variations of data and how to handle them. Using this tool, we can group values within a field together manually. This gives us the ability to bring together values that we recognize as being the same but have been stored with minor inconsistencies. For example, in a field called [category] we could change the saved values
- Appointment
- Appt
- Apppointment ( misspelling intentional) so only the correct value of "Appointment" is saved, rather than any of the variations we have identified. This is an ext
About the Author: Tim Costello is a senior data architect focused on the data warehouse life cycle, including the design of complex ETL (Extract, Transform, Load) processes, data warehouse design and visual analytics with Tableau. He has been actively involved with Tableau for almost 10 years. He founded the Dallas/Fort Worth Tableau user group. He has delivered hundreds of Tableau classes online and in person all over the USA and Canada.
When Tim isn't working with data, he is probably peddling his bicycle in circles around DFW airport in Dallas, Texas. He aspires to be a long distance rider and enjoys going on rides ranging over several days and hundreds of miles at a time.
Lori Blackshear is a senior business process architect and expert at facilitating meaningful and productive communication between business and technology groups. She has deep experience in healthcare (human and veterinary), software development, and research and development in support of emergency services.
Lori served as a paramedic in Fort Worth, Texas and Nashville, Tennessee before shifting careers to helping people solve problems with data. When Lori isn't pondering business processes, she is active in the Fort Worth Civic Orchestra (violin) and the East Fort Worth Community Jazz band (tenor saxophone).
