> "That's after you set up users, schemas, tables, columns, oddly-named datatypes with unexpected behaviors, etc."

You shouldn't jump in at the deep end when learning this stuff, getting a feel for how an existing database works before creating your own is helpful, and you can download sample databases to play around with when you start learning if you don't have access to one already. Aside from this recommendation, if you're starting out learning about RDBMS, then SQlite is a good starting point, and the setup of a SQlite database is fairly simple.

If you're starting from scratch with a brand new database, here are some of the SQL keywords you'll find useful:

CREATE TABLE

ALTER TABLE

DELETE TABLE

TRUNCATE TABLE

INSERT INTO

UPDATE

SET

DELETE FROM

VARCHAR

INT

DECIMAL

PRIMARY KEY

FOREIGN KEY

REFERENCES

Furthermore, if you're using a decent DB GUI frontend, you don't even need to remember most of the above, aside from VARCHAR (for strings), INT (for whole numbers) and DECIMAL (for numbers with a fractional element). Reason being, you can do all of the database setup graphically. Tools like SQL Server Management Studio help in reducing friction.