Book Image

Data Wrangling with Python

By : Dr. Tirthajyoti Sarkar, Shubhadeep Roychowdhury
Book Image

Data Wrangling with Python

By: Dr. Tirthajyoti Sarkar, Shubhadeep Roychowdhury

Overview of this book

For data to be useful and meaningful, it must be curated and refined. Data Wrangling with Python teaches you the core ideas behind these processes and equips you with knowledge of the most popular tools and techniques in the domain. The book starts with the absolute basics of Python, focusing mainly on data structures. It then delves into the fundamental tools of data wrangling like NumPy and Pandas libraries. You'll explore useful insights into why you should stay away from traditional ways of data cleaning, as done in other languages, and take advantage of the specialized pre-built routines in Python. This combination of Python tips and tricks will also demonstrate how to use the same Python backend and extract/transform data from an array of sources including the Internet, large database vaults, and Excel financial tables. To help you prepare for more challenging scenarios, you'll cover how to handle missing or wrong data, and reformat it based on the requirements from the downstream analytics tool. The book will further help you grasp concepts through real-world examples and datasets. By the end of this book, you will be confident in using a diverse array of sources to extract, clean, transform, and format your data efficiently.
Table of Contents (12 chapters)
Data Wrangling with Python
Preface
Appendix

Introduction


This chapter of our data journey is focused on RDBMS (Relational Database Management Systems) and SQL (Structured Query Language). In the previous chapter, we stored and read data from a file. In this chapter, we will read structured data, design access to the data, and create query interfaces for databases.

Data has been stored in RDBMS format for years. The reasons behind it are as follows:

  • RDBMS is one of the safest ways to store, manage, and retrieve data.

  • They are backed by a solid mathematical foundation (relational algebra and calculus) and they expose an efficient and intuitive declarative language – SQL – for easy interaction.

  • Almost every language has a rich set of libraries to interact with different RDBMS and the tricks and methods of using them are well tested and well understood.

  • Scaling an RDBMS is a pretty well-understood task and there are a bunch of well trained, experienced professionals to do this job (DBA or database administrator).

As we can see in the following...