When I first attempted to publish to F-Droid, I experienced several pipeline issues. After reading through the pipeline logs in GitLab, I realized that my application's database (ObjectBox) was not entirely FOSS compliant and was causing build failures. The following day was spent migrating my app to Room. - Source: dev.to / 8 months ago

I would focus on Kotlin instead of Java, there's really no point in sticking to Java at this point. And when it comes to databases, some local ones that are pretty easy to get into are Realm and ObjectBox, SQLite can definitely be a bit overwhelming at the beginning. Source: about 1 year ago

Just to add to this, there's also Realm and ObjectBox as alternatives. Source: over 1 year ago

Adding ObjectBox [0] to the list. [0] https://objectbox.io/. - Source: Hacker News / almost 2 years ago

While - strictly speaking - "database" refers to a systematic collection of data, "Database Management System'', or DBMS, refers to the piece of software that provides an efficient and versatile method of working with data(eg: ObjectBox). However, often the term "database" is also used loosely to refer to a DBMS, and you will find most DBMS only use the term database in their name and communication. - Source: dev.to / almost 2 years ago

I actually worked on a project that did this. We used a database called "Tile38" [1] which used an R-Tree to make geospatial queries speedy. It was pretty good. Our dataset was ~150 GiB, I think? All in RAM. Took a while to start the server, as it all came off disk. Could have been faster. (It borrowed Redis's query language, and its storage was just "store the commands the recreate the DB, literally", IIRC. Dead... - Source: Hacker News / almost 2 years ago