One of the weirdest things to me about cryptocurrencies is they appear to select for fans who are either hypercompetent at technology or totally clueless, but nobody who e.g. knows what a database is but doesn't use one professionally.
I feel compelled to ask: "Quick question: is your blockchain written in SQL?" just to disambiguate.
If you get "No, but actually kinda yes, but wait that question is too poorly formed to even be answered" you have someone who actually knows how 1+ clients work at a non-superficial level.
Actually come to think of it BerkeleyDB doesn't expose a SQL interface, does it? That may not be technically accurate. (Blockchain is theoretically a data structure but they're actually inextricably linked to particular client implementations which typically depend on local DBs.)
