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You're reading from  SQL for Data Analytics

Product typeBook
Published inAug 2019
Reading LevelIntermediate
PublisherPackt
ISBN-139781789807356
Edition1st Edition
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Authors (3):
Upom Malik
Upom Malik
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Upom Malik

Upom Malik is a data science and analytics leader who has worked in the technology industry for over 8 years. He has a master's degree in chemical engineering from Cornell University and a bachelor's degree in biochemistry from Duke University. As a data scientist, Upom has overseen efforts across machine learning, experimentation, and analytics at various companies across the United States. He uses SQL and other tools to solve interesting challenges in finance, energy, and consumer technology. Outside of work, he likes to read, hike the trails of the Northeastern United States, and savor ramen bowls from around the world.
Read more about Upom Malik

Matt Goldwasser
Matt Goldwasser
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Matt Goldwasser

Matt Goldwasser is the Head of Applied Data Science at the T. Rowe Price NYC Technology Development Center. Prior to his current role, Matt was a data science manager at OnDeck, and prior to that, he was an analyst at Millennium Management. Matt holds a bachelor of science in mechanical and aerospace engineering from Cornell University.
Read more about Matt Goldwasser

Benjamin Johnston
Benjamin Johnston
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Benjamin Johnston

Benjamin Johnston is a senior data scientist for one of the world's leading data-driven MedTech companies and is involved in the development of innovative digital solutions throughout the entire product development pathway, from problem definition to solution research and development, through to final deployment. He is currently completing his Ph.D. in machine learning, specializing in image processing and deep convolutional neural networks. He has more than 10 years of experience in medical device design and development, working in a variety of technical roles, and holds first-class honors bachelor's degrees in both engineering and medical science from the University of Sydney, Australia.
Read more about Benjamin Johnston

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Using Aggregates to Clean Data and Examine Data Quality

In Chapter 2, The Basics of SQL for Analytics, we discussed how SQL can be used to clean data. While the techniques in Chapter 2, The Basics of SQL for Analytics for Analytics, do an excellent job of cleaning data, aggregates add a number of techniques that can make cleaning data even easier and more comprehensive. In this section, we will look at some of these techniques.

Finding Missing Values with GROUP BY

As mentioned in Chapter 2, The Basics of SQL for Analytics, one of the biggest issues with cleaning data is dealing with missing values. While in Chapter 2, The Basics of SQL for Analytics, we discussed how to find missing values and how we could get rid of them, we did not say too much about how we could determine the extent of missing data in a dataset. Primarily, it was because we did not have the tools to deal with summarizing information in a dataset – that is, until this chapter.

Using aggregates, identifying...

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SQL for Data Analytics
Published in: Aug 2019Publisher: PacktISBN-13: 9781789807356

Authors (3)

author image
Upom Malik

Upom Malik is a data science and analytics leader who has worked in the technology industry for over 8 years. He has a master's degree in chemical engineering from Cornell University and a bachelor's degree in biochemistry from Duke University. As a data scientist, Upom has overseen efforts across machine learning, experimentation, and analytics at various companies across the United States. He uses SQL and other tools to solve interesting challenges in finance, energy, and consumer technology. Outside of work, he likes to read, hike the trails of the Northeastern United States, and savor ramen bowls from around the world.
Read more about Upom Malik

author image
Matt Goldwasser

Matt Goldwasser is the Head of Applied Data Science at the T. Rowe Price NYC Technology Development Center. Prior to his current role, Matt was a data science manager at OnDeck, and prior to that, he was an analyst at Millennium Management. Matt holds a bachelor of science in mechanical and aerospace engineering from Cornell University.
Read more about Matt Goldwasser

author image
Benjamin Johnston

Benjamin Johnston is a senior data scientist for one of the world's leading data-driven MedTech companies and is involved in the development of innovative digital solutions throughout the entire product development pathway, from problem definition to solution research and development, through to final deployment. He is currently completing his Ph.D. in machine learning, specializing in image processing and deep convolutional neural networks. He has more than 10 years of experience in medical device design and development, working in a variety of technical roles, and holds first-class honors bachelor's degrees in both engineering and medical science from the University of Sydney, Australia.
Read more about Benjamin Johnston