There is a difference between Database and Database Management System.
The Database is a collection of database, basically you store all your data in a database, the differential is how you insert, manipulate and remove data from there, this is the role of the Management System (DBMS).
If you want to store data without using a DBMS you will need to create one of your own. This can be summed up in opening a file, writing the data and closing the file, By concentrating you will be squandering the Distributed System properties that some Dbms offer (if not all), in addition to the so-called ACID (relational database) and BASE property (non-relational database or Nosql).
Basically you can have a file just for you to write and leave there in a corner if you want, but be aware that you will need to work mainly in atomicity (protect your data from failures) which will take a lot of work.
My suggestion: use a relational database or a Nosql, see which one best meets your needs, if you’re not using a specific data too much, don’t use it, Dbms are smart enough about it, In the case of the relational database there is the concept of Materialized View, you could take advantage of it. If you’re going to use a die a lot, use it, they’re also smart for it and make it easy to access your data. They also offer ROLES (access privileges), concurrent accesses, Raids, all of which you lose by not using a DBMS, and if you use your own data manipulation method, you would have to teach this to your entire team.
Do not invent the wheel, at most search by Nosql https://pt.wikipedia.org/wiki/NoSQL
– Motta
The question may not ask for good practice, but it is perfectly valid.
– utluiz
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– Maniero