Book Image

SQL for Data Analytics

By : Upom Malik, Matt Goldwasser, Benjamin Johnston
3 (1)
Book Image

SQL for Data Analytics

3 (1)
By: Upom Malik, Matt Goldwasser, Benjamin Johnston

Overview of this book

Understanding and finding patterns in data has become one of the most important ways to improve business decisions. If you know the basics of SQL, but don't know how to use it to gain the most effective business insights from data, this book is for you. SQL for Data Analytics helps you build the skills to move beyond basic SQL and instead learn to spot patterns and explain the logic hidden in data. You'll discover how to explore and understand data by identifying trends and unlocking deeper insights. You'll also gain experience working with different types of data in SQL, including time-series, geospatial, and text data. Finally, you'll learn how to increase your productivity with the help of profiling and automation. By the end of this book, you'll be able to use SQL in everyday business scenarios efficiently and look at data with the critical eye of an analytics professional. Please note: if you are having difficulty loading the sample datasets, there are new instructions uploaded to the GitHub repository. The link to the GitHub repository can be found in the book's preface.
Table of Contents (11 chapters)
9
9. Using SQL to Uncover the Truth – a Case Study

1. Understanding and Describing Data

Activity 1: Classifying a New Dataset

Solution

  1. The unit of observation is a car purchase.
  2. Date and Sales Amount are quantitative, while Make is qualitative.
  3. While there could be many ways to convert Make into quantitative data, one commonly accepted method would be to map each of the Make types to a number. For instance, Ford could map to 1, Honda could map to 2, Mazda could map to 3, Toyota could map to 4, Mercedes could map to 5, and Chevy could map to 6.

Activity 2: Exploring Dealership Sales Data

Solution

  1. Open Microsoft Excel to a blank workbook.
  2. Go to the Data tab and click on From Text.
  3. Find the path to the dealerships.csv file and click on OK.
  4. Choose the Delimited option in the Text Import Wizard dialog box, and make sure to start the import at row 1. Now, click on Next.
  5. Select the delimiter for your file. As this file is only one column, it has no delimiters, although CSVs traditionally...