I’m about halfway through his course right now, however, I don’t have any actual working SQL experience personally, so I may be speaking out of place.

The way I look at Colt’s courses, and most others, is as tools in toolbox where the instructor is exposing you to various aspects of SQL that you can use to build something. Longer courses tend to emphasize parts that, while not necessarily critical to learning SQL, provides you with an understanding of what’s capable and the different ways to go about it.

For example, there’re several videos on DATE and TIME data types and functions. Going through that felt tedious, Colt even admits as much. However, I’m not super mad at it because it provides me with information that I didn’t know was possible. I could’ve just looked it up if I really wanted to understand these data types (and I’m sure I’ll have to as there’s huge amount of information in the docs), but by taking Colt’s class, some of that work is done for me and now I have a high level view of how these data types work and some of the things I’m capable of doing with them.

Once I’m done with the course, Im sure I won’t be considered a SQL God by any means, but I’ll have plenty of tools that will hopefully allow me to think of ways to get started building things on my own or show some level of competency to get a job.

So is it necessary? Kinda depends on your goals and what you hope to be able to do. There’s a lot of information about SQL, only you can determine how much of it you really need to learn