The Best Websites to Learn & Practice SQL
If you’re new to the wonderful world of data, be it analytics, engineering, science, or database management, then you are bound to have come across the three letter acronym SQL once or twice (or hundreds of times). If you are interacting with organized data in a corporate setting, chances are you will need to learn, and potentially master, the art of writing SQL database queries. Structured Query Language, or SQL for short, is a domain-specific coding language used for managing, accessing, organizing, and downloading data held in a relational database management system. It has become the industry standard for a vast majority of the world, and learning to love its simplicity will serve you well in your career.
In terms of the best approach to getting started, below are a few websites that I found to be the most effective at learning and practicing SQL queries. The resources below will get you to a level of competence high enough to apply to any job with the term SQL under required skills.
Learn
DataCamp — datacamp.com/courses/introduction-to-sql
DataCamp is a well known website offering courses in many coding languages and data-related fields. Naturally, they have a great (and free!) 4 hour introductory course for learning SQL. I would suggest starting here, as they do a great job covering the how’s and why’s before digging into the actual code and database management stuff.
SQL Zoo — sqlzoo.net
After you have a good idea of what SQL is and how it’s used, SQL Zoo is your best next stop. I think you would be hard pressed to find a better website out there for learning SQL from scratch. It is actually shocking how simple and perfectly organized their process for learning the basics of writing queries is. They start you out going down a large list of interactive tutorials, each of of which give you a visual data table to inspect, as well as step-by-step examples that allow you to write your own queries.
Practice
SQL Fiddle — sqlfiddle.com
SQL Fiddle is a great website that provides access to the syntax of multiple DBMS types — SQL Server, Oracle, MySQL, and more. They do have reasonable limitations in storage size and query runtime, but those limits likely won’t affect you as you are using it to practice. Another advantage is you can access it from a mobile device and do quick syntax, design checks, and experiments from anywhere. Find yourself mindlessly scrolling through Facebook? Knock out some SQL queries instead!
HackerRank — hackerrank.com/domains/sql
You’ve probably heard of HackerRank before, so it should be no surprise to you that they have one of the best collections of SQL practice challenges around. They offer about 60 code challenges using different types of data, and they order them in a structured way to build off of each other; increasing in difficulty and complexity as you are are introduced to more and more concepts.
There are many more websites and blogs that offer ways to practice SQL, but the ones above will certainly get you started in the right direction. Do you know of any sites I should mention? Feel free to leave a comment/suggestion below!