Where to start learning SQL?

Question

Database

I started to study the database on this site: https://site-do.ru/db/ (SQL-MySQL)
And then, suddenly, I began to understand that there are different environments, roughly speaking, and dialects of the language
. Did I start the database (through that site)?
I don't want to waste my time learning something I don't need.

Answer 1

there are different environments, roughly speaking and dialects of the language

the difference is so insignificant for you that you don't even need to bother with this topic. to solve 80% of problems, developers write very typical standardized SQL. don't even bother with this.

Answer 2

I don't want to waste my time learning something I don't need.

This is what constantly surprises me with beginners - they are afraid to learn something they don’t need, before they even start learning something.
Until you have reached at least the level of a middle developer, you should not discard anything. Then you can really assess for yourself what is needed and what is not.
And up to this level - any knowledge will only add experience and intuition to you.

Answer 3

sql-ex.ru
Two mushroom pickers got lost. Barely moving their legs, they went to the edge.
And there is an ensign. They ask him:
- Comrade military man, are we going to the station right?
- Yes, which one is correct? The ankle wobbles, the impact of the foot is not clear, and generally not in the leg ...

Answer 4

Some other dull selection of articles from Vasyan.
I would still recommend the book, there are a lot of them and the information in them is the most complete.

Answer 5

For example:
Martin Graber, sql for mere mortals

Answer 6

Alan Bewley has a good book - small (~300 pages), there are separate digressions about dialects (opportunities of Oracle, Postgres, MS SQL and MySQL)