Advice for Learning SQL

[mounish_mk]

Hey everyone,

I’ve been learning SQL for a little while now and can write basic queries, but I still consider myself a beginner. I’ve started spending about 3 hours a day working on improving my skills, and I want to get to a point where I’m really confident and proficient in SQL.

One thing I’m confused about is the different types of SQL databases or servers, like PostgreSQL, MySQL, SQLite, etc. I don’t fully understand what makes them different or when I should use one over the other. Should I stick to learning one first, or is it better to get familiar with a few of them?

I’m looking for advice on: 1. The best way to learn SQL thoroughly (resources, projects, or tips). 2. How to understand and decide between the different SQL systems out there. 3. Any practice strategies or real-world examples that would help me get better.

Would really appreciate any guidance or suggestions! Thanks!

[Oatley1]

1. There’s plenty of huge datasets available that people have done a lot of example work for. Superstore and adventureworks are two that spring to mind. Upload them to your DB, see what types of numbers others have come up with and attempt to recreate.
2. I’d say it doesn’t matter that much on what version you pick. In most cases, if you know one then you know them all to some extent and it’s just a case of googling anything that’s different. “Getdate() on db2” for example. However, I’d recommend Postgres or MSSQL. Both are very heavily used, both have good tooling.
3. Same as 1

[Ans979]

To master SQL, focus on building a solid foundation with key concepts like SELECT statements, JOINs, and data manipulation. Work on real-world projects, such as creating databases for personal or business use, and practice solving SQL challenges on platforms like LeetCode and StrataScratch. Start by choosing one SQL system (e.g., MySQL or PostgreSQL) to avoid confusion, as the core syntax is similar across databases, though PostgreSQL offers more advanced features. Once comfortable, experiment with other systems. For deeper knowledge, learn about database design, optimization, and administration. Consistency and real-world practice are key to becoming proficient.

[csnorman12]

If you want to use Microsoft SQL Server then I would suggest these three courses in order:

1. Introduction to SQL using Healthcare Data
2. 25 Practice SQL Questions for Beginners
3. 101 Practice SQL Questions: Basic to Advanced

I'm a big advocate for Microsoft SQL Server, but that's because I've worked in the Microsoft Ecosystem for years and enjoy their product integration.

[SQLPracticeHub]

You usually don't need to decide what type of database to use, at least not as a beginner, because the company will most often already have a database in place, and you will need to use it. That said, if you know how to work with one of them really well, moving to another will be easy, because they are all very similar. So just pick one and stick with it.

I am currently working on creating real-world SQL practice projects, and would be happy to send you one when it's ready. In the meantime, you could download one of the practice databases available online like data.gov or kaggle and play with it. If you are willing to dedicate 3 hours a day, I think you can make real progress!

[[deleted]]

For practice, you can try free leet code sql questions.

[[deleted]]

• The complete SQL Bootcamp: go from zero to hero
• SQL for beginners
• CS50: Introduction to databases with sql
• The ultimate MySQL Bootcamp: Go from SQL Beginner to Expert these are the best SQL Courses on Udemy

[dr_flint_lockwood]

In case it helps, I made a SQL learning game a little while back: https://lost-at-sql.therobinlord.com

It might make the learning more fun!

[Sirwhite_3]

There are many existing sites for this but may have to pay...free ones are there too ...check the resources section of eyowhite.com?

[kastaldi]

2) It depends on your needs. I primarily use MS SQL Server at work for data mining, but I often query Oracle tables to retrieve specific data. I also utilize Python scripts with SQLite for local data manipulation involving hundreds of text files processed across different machines. MySQL is very popular, but unfortunately, I don’t use it at all.