Thanks; here’s my blog post: http://blog.sagemath.com/2017/02/09/rethinkdb-vs-postgres.ht...

Incidentally, http://www.lmfdb.org uses MongoDB (since maybe 2011) pretty heavily, as a result of me convincing them to do so after I read too much about MongoDB back then. It’s been painful for them, but it does still work well...