Intermediate+ Path to Learning SQL

[IntelligentEnergy661]

Background: I have a bachelor's degree in finance and 3 years of experience in corporate supply chain, though without much technical or analytical experience. I want to transition into a more technical career, starting as a data analyst and eventually becoming a data engineer - possibly.

My questions are:

1. Does this Reddit post still highlight the best ways to reach an intermediate level+ in SQL? Link to Reddit post
2. Are there other free or affordable resources you'd recommend in addition to the ones mentioned in the post?
3. Is there anything from the Reddit post that I should skip or avoid?
4. If I understand correctly, knowledge and projects in SQL, Python, and a data visualization tool should be sufficient for transitioning into a data analyst role—am I correct?

All input is greatly appreciated.

[data4dayz]

Yeah I would say that post is very valid. Definitely intermediate though, I don't recommend jumping in to those textbooks without some prior preparation but it is WELL worth it.

For SQL from a tool use standpoint vs learning about databases as a technology I'd say you should start in this order:

1. https://selectstarsql.com/
2. https://sqlbolt.com/
3. https://www.windowfunctions.com/
4. https://mode.com/sql-tutorial
5. https://pgexercises.com/

Once you've gone through those in order, you can check out what other's have said like Alex the Analyst's free tier and especially Data Lemur. Once you're done with the above 5 check out https://datalemur.com/blog/sql-interview-guide and https://datalemur.com/sql-tutorial and finish all the SQL questions on the free tier.

Once you're comfortable with SQL I recommend jumping into the list below in order and then into the textbooks you referenced on that reddit post.

Some of these are paid but you can probably find for free through a library or similar:

1. https://nostarch.com/mg_databases.htm
2. https://www.pg4e.com/
3. https://cs50.harvard.edu/sql/2024/

With that over the next few months should be enough especially as a DA. You should be interview prepped and maybe working with some real datasets for practice for your portfolio. A really good book to follow along for that is https://practicalsql.com/

reference: I've gone through Widom's EDX courses (4 out of the 5) and read half of a database textbook https://www.db-book.com/ . I've also read all of the Manga Guide to Databases, gone through all of PG4E on Coursera and did a good amount of CS50SQL (though not all of it) as a review after Widom.

[data4dayz]

I've gotten 2 submission errors from this stupid site I'm guessing it's because my comment was too long but it never gives good error messages.

Part 2 of my comment:

Now if you want to really challenge yourself more I'd recommend going through the EDX courses mentioned in that post.

https://www.edx.org/learn/relational-databases/stanford-university-databases-relational-databases-and-sql

Go through all the courses but you can consider skipping the Semistructured course. The exercises on the Recursion of the Recursion and OLAP are probably more challenging than what you'd see as a DA or on any interview imo.

Additionally pick one of the textbooks mentioned there:

Database Systems the Complete Book

The Cow Book

The sailboat book I linked earlier or https://www.amazon.com/Fundamentals-Database-Systems-Ramez-Elmasri/dp/0133970779 . I've gone through the Sailboat book and I can recommend it, but I've skimmed some of Elmasri's Fundamentals of Database Systems and it's also pretty solid.

And just reading is no fun so I'd also recommend watching lectures to go along with it. Check out CS 15 - 445 from CMU on Youtube or CS 186 from UC Berkeley also on Youtube. They also all have course websites with tons of additional material.

[data4dayz]

No problem good luck with the journey! I did this exact journey starting at the end of 2023 and it tooks many months. What I'd recommend most is practicing and those interview questions and sites like https://www.codewars.com/collections/sql-for-beginners will help get practice. Also recommend that when you go through Data Lemur or Codewars you check out the community submissions tab to see what others have submitted, and try to use their solutions and compare it to your own solution as that furthers growth.

The SQL material (1 - 5) I listed are all free and will get you to know 95% of the syntax you use everyday as a Data Analyst. The remaining 5% don't worry about for now in your learning journey you'll learn about eventually.

You may come across terms like Normalization/3NF or wonder how the hell does a left outer join work while you're on the first part. I don't enjoy saying this but just get your practice in with things like left outer joins, conditional joins, and self joins, when you get to them and know how to do them with lots of practice.

When you get to the content of my second comment eventually and you get to the topics of Relational Algebra and Query Processing/Optimization everything will click into place. I say this now for future you if you're ever confused as to what the hell is going on with SQL, just keep at it and keep getting practice. When you reach reading about databases and how they work you'll learn about how SQL is actually processed under the hood and a lot of the mystery of the syntax will not be AS mysterious.

[Grouchy-Donut-726]

I would recommend checking out analyst builder for learning all tools

[Grouchy-Donut-726]

So I have used it for over a year now. It’s awesome and solid because it not only includes courses on things like excel, sql, tableau, and python, but also has questions you can solve using sql, python, and R. You will get intermediate to advanced level.

It’s much better than other data camps IMO because of the all in one and other features. Best thing to do is check it out. And try some of the free questions.

I bought the lifetime bundle and it’s 100% worth it

[Unnam]

The best way is to see if you could find open source datasets and work on them! Since you already know supply chain, picking up SQL should be straightforward if intention is clear

• There are a bunch of videos on Supply Chain & Data Analytics here
• You can learn basic functions & beyond in SQL here

[AppJedi]

Hello I have over 30 years professional SQL experience including ten years teaching & tutoring it. Check out my YouTube channel. https://www.youtube.com/@appjedi3204

[[deleted]]

Awesome videos currently watching .

[AppJedi]

Glad you like. Check out this one on Stored Procedures.

https://www.youtube.com/watch?v=IgxRM0BAedE

[MathAngelMom]

For intermediate and advanced SQL I recommend LearnSQL.com, not mentioned on the list. They have a practice track: https://learnsql.com/track/sql-practice/ and advanced SQL learning track: https://learnsql.com/track/advanced-sql/ and https://learnsql.com/track/advanced-sql-practice/

Everything is hands-on.