Data Wrangling with SQL: A hands-on guide to manipulating, wrangling, and engineering data using SQL

Become a data wrangling expert and make well-informed decisions by effectively utilizing and analyzing raw unstructured data in a systematic manner

Purchase of the print or Kindle book includes a free PDF eBook
Key Features

Implement query optimization during data wrangling using the SQL language with practical use cases
Master data cleaning, handle the date function and null value, and write subqueries and window functions
Practice self-assessment questions for SQL-based interviews and real-world case study rounds

Book Description

The amount of data generated continues to grow rapidly, making it increasingly important for businesses to be able to wrangle this data and understand it quickly and efficiently. Although data wrangling can be challenging, with the right tools and techniques you can efficiently handle enormous amounts of unstructured data.

The book starts by introducing you to the basics of SQL, focusing on the core principles and techniques of data wrangling. You’ll then explore advanced SQL concepts like aggregate functions, window functions, CTEs, and subqueries that are very popular in the business world. The next set of chapters will walk you through different functions within SQL query that cause delays in data transformation and help you figure out the difference between a good query and bad one. You’ll also learn how data wrangling and data science go hand in hand. The book is filled with datasets and practical examples to help you understand the concepts thoroughly, along with best practices to guide you at every stage of data wrangling.

By the end of this book, you’ll be equipped with essential techniques and best practices for data wrangling, and will predominantly learn how to use clean and standardized data models to make informed decisions, helping businesses avoid costly mistakes.
What you will learn

Build time series models using data wrangling
Discover data wrangling best practices as well as tips and tricks
Find out how to use subqueries, window functions, CTEs, and aggregate functions
Handle missing data, data types, date formats, and redundant data
Build clean and efficient data models using data wrangling techniques
Remove outliers and calculate standard deviation to gauge the skewness of data

Who this book is for

This book is for data analysts looking for effective hands-on methods to manage and analyze large volumes of data using SQL. The book will also benefit data scientists, product managers, and basically any role wherein you are expected to gather data insights and develop business strategies using SQL as a language. If you are new to or have basic knowledge of SQL and databases and an understanding of data cleaning practices, this book will give you further insights into how you can apply SQL concepts to build clean, standardized data models for accurate analysis.
Table of Contents

Database Introduction
Data Profiling and Preparation before Data Wrangling
Data Wrangling on String Data Types
Data Wrangling on the DATE Data Type
Handling NULL values
Pivoting Data Using SQL
Subqueries and CTEs
Aggregate Functions
SQL Window Functions
Optimizing Query Performance
Descriptive Statistics with SQL
Time Series with SQL
Outlier Detection