Completing CS50’s Introduction to Databases with SQL

At the end of May, just after finishing my university semester, I wanted to keep learning and stay active. After a small SQL project intended as a refresher (which I may post about later), I decided to push myself further by starting CS50’s Introduction to Databases with SQL. From early June to early July, I worked through the course and completed it, my first big step in strengthening my database skills in a structured way.

Unlike a one-off tutorial, CS50 gave me a steady routine of SQL practice over several weeks. That consistency helped turn what I’d learned previously into habits I could build on.

Why I Took It

• I wanted a structured way to reinforce the basics I’d started exploring on my own.
• I learn best by doing, so the problem sets gave me a steady rhythm of practice.
• I wanted a recognised milestone I could include in my portfolio and CV.

How I Studied

• I set aside small blocks of time most days rather than long weekend sessions.
• I kept simple notes as I went, just enough to remind myself of the “why,” not just the “how.”
• When I got stuck, I rebuilt small examples from scratch until the concepts felt natural.

Final Project

The course ends with a small project. For mine, I created an enhanced version of my Caves & Creatures database — this time improving schema design, constraints, and more structured queries than in my first attempt.

If you’d like to see any of the exercises or projects, I’ve uploaded them here: github.com/deancoles/CS50_SQL.

What I Learned

• Foundations that stick - setting up the right keys and constraints early makes later queries much easier.
• Thinking in relationships - planning how tables connect is just as important as writing the SQL itself.
• Writing for clarity - views and CTEs don’t just solve problems, they make queries easier to maintain and understand.
• Confidence - regular practice over a month gave me the rhythm I needed to feel at home with SQL.

What’s Next

• Work on more small projects that showcase practical query design and reporting.
• Strengthen my analysis skills further by combining SQL with tools like Power BI.
• Apply what I’ve learned in my wider software engineering work, so both paths develop together.

CS50’s Introduction to Databases with SQL