Book Image

Building ETL Pipelines with Python

By : Brij Kishore Pandey, Emily Ro Schoof
5 (1)
Book Image

Building ETL Pipelines with Python

5 (1)
By: Brij Kishore Pandey, Emily Ro Schoof

Overview of this book

Modern extract, transform, and load (ETL) pipelines for data engineering have favored the Python language for its broad range of uses and a large assortment of tools, applications, and open source components. With its simplicity and extensive library support, Python has emerged as the undisputed choice for data processing. In this book, you’ll walk through the end-to-end process of ETL data pipeline development, starting with an introduction to the fundamentals of data pipelines and establishing a Python development environment to create pipelines. Once you've explored the ETL pipeline design principles and ET development process, you'll be equipped to design custom ETL pipelines. Next, you'll get to grips with the steps in the ETL process, which involves extracting valuable data; performing transformations, through cleaning, manipulation, and ensuring data integrity; and ultimately loading the processed data into storage systems. You’ll also review several ETL modules in Python, comparing their pros and cons when building data pipelines and leveraging cloud tools, such as AWS, to create scalable data pipelines. Lastly, you’ll learn about the concept of test-driven development for ETL pipelines to ensure safe deployments. By the end of this book, you’ll have worked on several hands-on examples to create high-performance ETL pipelines to develop robust, scalable, and resilient environments using Python.
Table of Contents (22 chapters)
1
Part 1:Introduction to ETL, Data Pipelines, and Design Principles
Free Chapter
2
Chapter 1: A Primer on Python and the Development Environment
5
Part 2:Designing ETL Pipelines with Python
11
Part 3:Creating ETL Pipelines in AWS
15
Part 4:Automating and Scaling ETL Pipelines

Loading data into PostgreSQL tables

To complete the data pipeline, you need to load the transformed data into the final output locations – the PostgreSQL data tables – so that your client can easily access and use them. In this section, you will load the cleaned data into the PostgreSQL chicago_dmv schema using the psycopg2 Python module. As you may recall from the previous chapter, psycopg2 is a Python package that enables you to connect your Python (or Jupyter Notebook) script to PostgreSQL. Use the following code to establish a connection to the database from your Jupyter Notebook:

import psycopg2# Establish connection to the Postgresql database
conn = psycopg2.connect(database="your_database_name",
    user="your_username", password="your_password",
    host="your_host", port="your_port")
# Create a cursor object
cur = conn.cursor()

Using SQL statements in Python, denoted...