> I've always assumed that PostgreSQL, but never really bothered to look into what I get for the effort.
You're making a (mistaken) assumption that Postgres giving you a "step up" means that you also have to put in more effort. You don't, at least not in my experience. Both are database servers with a bunch of install & setup. There's phppgadmin if you want an 1:1 replacement for phpmyadmin (no opinion on these, haven't used either).
Postgres just gets you farther if you need to at a later point.
I would recommend you swap out mysql for postgres on your raspis. You're gaining experience on one of the two. But experience on Postgres seems to be more useful and valuable (cf. rest of the HN comments), for the same cost of your time.
You're making a (mistaken) assumption that Postgres giving you a "step up" means that you also have to put in more effort. You don't, at least not in my experience. Both are database servers with a bunch of install & setup. There's phppgadmin if you want an 1:1 replacement for phpmyadmin (no opinion on these, haven't used either).
Postgres just gets you farther if you need to at a later point.
I would recommend you swap out mysql for postgres on your raspis. You're gaining experience on one of the two. But experience on Postgres seems to be more useful and valuable (cf. rest of the HN comments), for the same cost of your time.