10 Websites to Learn Database and SQL in Depth

Hello Devs, SQL is one of the most essential skills in today's increasingly data-driven world. It's vital for any programmer like a Java, C++, Python, JavaScript, or Ruby developer and people learning Data Science and Data analysis.

You may not believe but in my 20 years of career as a Java developer, I found that almost 95% of Java applications use a relational database in their back-end, and nearly all web applications use the database. 

In recent years, one of the most common ways to learn any programming skill is learning online, in the comfort of the office or home, and SQL is no different. Learning SQL online has another advantage of a quick head start because you don't need to install a database and create tables to write some SELECT queries. 

The installation and setup are tricky for beginners, and I have gone through that pain every time I have to learn a new database.

Once you start writing queries and seeing the result, you feel that confidence needed to go to the next level, which involves downloading and installing a free copy of popular databases like MySQL, PostgreSQL, SQL Server, or Oracle on your machine.

From my experience, I can say that SQL is easy to learn but challenging to master. You can start writing SQL queries in about an hour or so, but it's not that easy to write questions to solve real-time requirements or for reporting purposes.

Practising SQL online on sites like SQLZoo or SQLFiddle will help you keep up-to-date and improve your SQL skills, which is the main challenge for any SQL developer or programmer.

10 Best Resources to Learn SQL Online for Free 

Here is my collection of the top five websites I found pleasing to learn and master SQL. There are many websites, blogs, and tutorials on the Internet, but at the same time, it isn't easy to find excellent resources.

Since I am passionate about collecting good resources for learning technology, I always bookmark my great discoveries. These websites are some of those.

1. Udemy

Udemy is one of the best websites to learn any technical skill for free in 2023. It has the most extensive collection of online courses, both free and paid. 

Since online courses are a great way to learn a new technology or programming language, you can also learn the basics of SQL and Databases.

Finding the right course is also a tough job because there are so many courses, and you are not sure which instructor is best and which system meets your requirements, so you need to watch previews, read reviews, and decide based on that.

The Complete SQL Bootcamp by Josh Portilla is the best course to learn SQL. It has, on average, 4.5 ratings from more than 127,000 students, which is impressive.

The only thing is that it's not free, but it is very affordable, as you can get them for less than $10 on Udemy's flash sale, which happens constantly. The course also provides certificates to indicate that you have completed the SQL training, adding to your resume or LinkedIn profile.

As I have said, Udemy also has many free courses to learn SQL and Database, and the following are my recommendations to start with.

1.  Introduction to Databases and SQL Querying--- 4.3 ratings from 175,000 Students
2.  Advanced Databases and SQL Querying--- 4.3 rating from approx 100,000 Students
3.  Oracle SQL --- A Complete Introduction--- 4.5 ratings from 25,000 Students
4.  Microsoft SQL Server --- An Introduction--- 4.4 ratings from 7,000 Students

You can take These excellent free courses on Udemy to learn SQL and Database fundamentals, querying, etc.

2. Coursera

Coursera is another place where you can learn in-demand tech skills for free. Many people don't know, but Coursera has many free courses, and most paid courses are also free to audit. They are the best websites to learn Data Science and have several valuable methods to learn essential Data Science skills like SQL.

Here are my favorite Coursera courses you can join to learn SQL for FREE:

1. SQL for Data Science --- the most popular SQL course on Coursera, and more than 330K people have already joined this course.

2. Introduction to Structured Query Language (SQL) --- This is another excellent SQL course on Coursera that the University of Michigan offers. It has, on average, 4.8 ratings, and more than 120K people have joined it.

3. Database Design and Basic SQL in PostgreSQL --- This one is for people who want to learn Database design and SQL in PostgreSQL, a popular SQL vendor. It's a relatively newer course but has, on average, 4.8 ratings.

4. Intermediate SQL--- This is another excellent PostgreSQL course from Coursera, which you can join for FREE. It's more for intermediate developers who are familiar with PostgreSQL. For example, you can join this after going through a previous course.

Overall, these are some of the best SQL courses from Coursera that you can take to learn this helpful tech skill. Most of them are either free or free-to-audit. When it comes to joining this course, you have two options; you can either enter this course alone, which costs around $39 per month for specialization, or you can also join Coursera Plus for $399 per year, a subscription plan from Coursera which gives you unlimited access to their most popular courses, specialization, professional certificate, and guided projects.

3. Codecademy

This is another excellent place or website to learn SQL for FREE. Codecademy was one of the first interactive websites I knew about, and since then, I have learned many vital skills like Linux bash, SQL, Java, and JavaScript on Codecademy.

Again most of their courses are free, but not all of them, and you need a Codecademy PRO membership to access their premium systems.

In this free SQL course, you'll learn how to communicate with relational databases through SQL. You'll know and practice with four projects --- how to manipulate data and build queries that communicate with multiple tables.

Here are things you will learn in this free SQL course on Codecademy:

1.  How to use SQL to access, create, and update data stored in a database.
2.  How to write complex queries by learning essential query keywords and functionality
3.  How to use powerful functions for performing complex database operations with ease.
4.  How to create and manipulate databases with multiple related tables

More than 1.2 million people have joined this free SQL course, and you can join too.

4. Datacamp

As the name suggests, this is a dedicated online website to learn Data skills like SQL. While it also has a subscription plan, not many people know that DataCamp also has many high-quality free courses to join to learn essential data skills for free.

The first chapter, "Filtering Columns," is entirely free. You'll learn about tables, columns, and rows in SQL, how to discuss them using database terminology, and how to begin an analysis using simple SQL commands to select and summarize columns from database tables.

And, If you are someone like me who knows SQL but always looking to increase knowledge and loves to try out some good SQL queries, check out Joe Celko's SQL Puzzles and Answers, Second Edition; it is one of the excellent resources to learn and master SQL programming.

5. Udacity

Udacity is another excellent online learning platform that offers courses and programs in various fields, such as data science, machine learning, artificial intelligence, programming, web development, and more. 

The platform offers free and paid courses, and learners can earn certificates or nano degrees upon completion.

Regarding SQL courses, Udacity does offer some free courses on SQL. For instance, they have a free lecture titled SQL for Data Analysis which teaches learners how to use SQL to manipulate data and perform data analysis tasks.

Additionally, they offer other SQL-related courses that may require payment, such as SQL Nanodegree or Data Analyst Nanodegree, which include more advanced SQL topics and skills.

6. Sqlzoo

SQLZoo is one of the best and most popular websites for learning SQL online. It provides both tutorials and exercises, and that's why it is equally helpful for someone just starting with SQL and programmers who know SQL but want some good practice to master it.

SQLZoo provides easy-to-understand tutorials and interactive examples to write queries and see results in your browser.

SQL interactive tutorials, examples, and exercises are on this website. It covers most SQL clauses like the SELECT clause to read data, CREATE to make a new database, ALTER to change the database, and DELETE to remove data and tables.

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It also covers advanced concepts like GROUP BY, Indexes, Views, SQL Joins, Sub-queries, handling NULL values in SQL, etc. SQLZoo also has several SQL quizzes to test your knowledge.

In short, this site is one of the best resources to learn and master SQL online, and it's FREE. Every programmer who has an interest in SQL can benefit from this site.

7. Freecodecamp

FreeCodecamp is another helpful place to learn tech skills. They have a website, freecodecamp.org, and a YouTube channel that is full of free but comprehensive courses, which is one of them.

This SQL course has over 7 million views, and I think it's YouTube's most popular free SQL course.

The course is designed for beginners in SQL and database management systems and will introduce common database management topics.

Throughout the course, you'll learn key SQL topics like schema design, basic C.R.U.D. operations, aggregation, nested queries, joins, keys, and more.

You can watch this course right here or on YouTube for FREE.

8. SQL Course From Stanford University

This is a free SQL course provided by Stanford University. This course contains good SQL video tutorials to explain both the primary and advanced concepts of SQL and Relational databases.

You can use this course in registered and non-registered mode, though it's better to get registered to save your progress. It's also a self-paced course so that you can learn quickly.

This website also provides free course material, e.g., SQL scripts, course slides, etc., which you can download from relevant sections. Given this course is from Stanford University, you can rest assured of quality.

9. SQL Course From Khan Academy

Khan Academy, one of the best websites to learn computer science and programming online, also has a good SQL tutorial titled "Intro to SQL: Querying and managing databases."

In this tutorial, you'll learn how to use SQL to store, query, and manipulate data. SQL is a special-purpose programming language designed for managing data in a relational database and is used by many apps and organizations.

I have used some tutorials from Khan Academy in the past, and this is one of them; it's like a virtual classroom. A good companion of SQLZoo makes your study complete. You can also get help from some good SQL books like Head First SQL if you are a beginner; the head first way is one of the best ways to learn SQL.

10. Sqlbolt

SQLBolt is another good website to learn SQL with simple, interactive examples. It contains interactive lessons and exercises designed to help you quickly learn SQL in your browser.

It contains 20 lessons starting from a basic SQL query to more advanced and confusing Join queries, aggregation, filtering, and dealing with nulls. It is one of the best resources to learn SQL for complete beginners.

So if you are the one who wants to learn SQL or you know SQL but don't feel comfortable, then go and try out SQLBolt's interactive SQL tutorials. SQLBolt also has SQL tasks after each lesson, forcing you to use the knowledge you learned in class.

The quality of queries is good, easy to start with, and getting difficult afterward. If you are stuck while writing an SQL query to solve the task, you can get help from their solution.

I suggest you finish the task as soon as you finish the lesson and then the next day do the job with some variation.

That's all about some of the best websites to learn SQL online for FREE. Though the Internet is full of free stuff, it's hard to find a good resource. I still respect curated resources and have benefited a lot from them. Though nothing can substitute classroom training, a combination of books, blogs, video tutorials, and interactive websites can help you get there.

Thanks for reading this article so far. If you like these websites to learn SQL online for FREE, please share them with your friends and colleagues. If you have any questions or feedback, then please drop a note.

P. S. -  If you are someone like me who knows SQL but always looking to increase knowledge and loves to try out some good SQL queries, check out  Joe Celko's SQL Puzzles and Answers, Second Edition; it is one of the excellent resources to learn and master SQL programming.