It [Roon] is using a noSQL database (some Google hack job, as I recall). It’s not text based, and performs pretty well, for what it is, but as pretty much any other noSQL (i.e. a rehash of 1960s tech that rightly went out of favor when better relational systems were designed [moderated]) it is OK for quick prototyping but not really appropriate for anything production-quality.
LevelDB:
Note the “Bugs and reliability” section
I’d sacrifice reliability over speed any day of the week. Unfortunately Roon often doesn’t manage either. Reliability at moment is poor it can’t be trusted to show anything correctly or even display the correct amount of albums in a library.
Well, it might have gotten better since 2014…but yeah, it’s not really a good choice for anything, and ironically it does not even seem to be a particularly good fit for Roon’s data model (which does map to relational very well, but somehow a lot of modern developers think that learning relational algebra is beneath them). There are some non-relational databases that would be a better match, too, like M, which also benefits of 60+ years of development and being used for critical, rather than just “ooh, Google scale!” operations.