How to Get Up and Running with SQL – A List of Free Learning Resources
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Considering that you clicked on this article, I can safely say that you are either just starting your data journey or are looking for ways to improve your SQL skills! Well you are in the right place and I will not disappoint you! In this article, you’ll get a quick background on SQL, including how and why it became popular, and some of the best free courses/resources I’ve found to start and keep improving your SQL skills!
Ever since two IBM researchers, Raymond Boyce and Donald Chamberlin, developed a new programming language in the 1970s, the data industry has relied heavily on SQL to effectively query and transform data. This became more apparent as data teams began moving their storage and data processing to cloud web servers.
With these changes, mastering this language has become increasingly important for anyone working on the analysis side of data. There’s a lot of noise on the internet about various cheat sheets offering the most basic SQL transformations. Based on my years of experience as a data analyst and data scientist, I can tell you that very few of these will help you in the long run. There are really only two ways to be effective with SQL – learn the basics and then hone your skills, or (the more popular ones) use other tools to increase productivity, with the sweet spot being a mix of the two is!
Udemy SQL course
Leading free course
Udemy is an online marketplace for learning and teaching with over 204,000 courses and 54 million students. The link above is a well-rounded course with a 4.5 rating and over 450,000 students have taken the course! In addition, this course requires no prior knowledge.
All SQL courses (paid)
PopSQL
List of SQL instructions
PopSQL is a modern SQL editor. It allows you to collaborate with colleagues and friends to write the right SQL queries. With such a strong foundation in concept, it only makes sense that they have good resources for people to learn SQL. In addition, this resource breaks down the different syntaxes, so you only have to work with the program you want. I recommend using this once you get a better understanding of the different transformations you are trying to perform.
W3Schools.com
SQL tutorial
W3Schools is one of the largest web development sites. It contains numerous courses on a variety of different programming languages. Your SQL tutorial will teach you MySQL, SQL Server, MS Access, Oracle, Sybase, Informix, Postgre and some other database systems. The beauty of this tutorial is that there are many examples and quizzes to test your knowledge with! In addition, they offer SQL references where you can find various keywords and functions. In this tutorial, you will receive a certificate that you can use to show that you have a basic understanding of SQL.
Khan Academy
Introduction to SQL: querying and managing data
Khan Academy is a 501(c)(3) non-profit organization and, like all of the resources listed above, is completely free. This is a beginner’s course that will teach you how to use SQL to store, query, and manipulate data in relational databases. This course offers you multiple videos, exciting challenges and quizzes at the end of the session to test your knowledge. While this requires a little more self-learning than some of the other resources listed above, it’s still an incredible resource for anyone looking to learn or practice their SQL skills.
Now that you’ve completed an introductory course in SQL and have a basic understanding of how queries are structured and the various transformations that are offered, you’re at a crossroads. You should know what you want to achieve and how to achieve it, but don’t have the time to search stackoverflow or google to round the corners of those specific queries. Here you will find various tools that will help you save time and work more efficiently. Below are two of my favorite resources that I recommend to any new or aspiring SQL user. These resources come from a recent article I published called “The Top 5 Bookmarks Every Data Analyst Should Have”.
beautify code
SQL formatter
There are a number of different SQL formatters on the web, but this is the one I use and enjoy. This tool is perfect for you and your colleagues as you no longer have to dig through extensive queries to find the transformation to perform. SQL Formatter instantly formats the query in a structured way that is easier to follow for both you and your colleague.
Essentially, the esthetician takes the following:
And turn it into this one!
Rasgo
Free SQL Generator
Even the most experienced SQL developer struggles to remember all the required syntaxes for various transformations. In response to this, many SQL users spend a lot of time searching through past projects or various online resources like Stackoverflow and forums looking for answers. For a data practitioner working in a data-centric company, saving time is almost as important as data quality.
I recommend using this SQL generator – “An SQL generator is basically a template for a SQL query that allows you to customize column names, table structures, choose the operation you want, and then build the syntax for you in a variety of different ones “Flavours” of SQL.”
I found a how-to blog here that explains how to use the SQL generator. Also, I recently noticed that my secret is being discovered; Suraj Gurav recently wrote a review of this SQL generator with examples entitled How To Write SQL Queries without Typing.
SQL is one of the most important programming languages to know when working with data and especially rotating databases. It may seem like a great relief when confronted with the programming language for the first time. Nonetheless, I hope that with the resources above, you can get a good basic understanding of the language from the free courses, and then use the other free resources to expand your knowledge/skills!
Josh Berry (@twitter) leads Customer Facing Data Science at Rasgo and has been in the data and analytics industry since 2008. Josh spent 10 years at Comcast where he built the data science team and was a key owner of the internally developed Comcast feature store – one of the first feature stores to hit the market. Post-Comcast, Josh was a key leader in building Customer Facing Data Science at DataRobot. In his spare time, Josh conducts complex analysis on interesting subjects such as baseball, F1 racing, housing market forecasts and more.