[danappelxx]

To clarify:

- I was talking about ACID guarantees across databases (ie across users) - I was talking about aggregations across databases (ie across users)

Of course working inside one database works as you would expect it to. My point was that this pattern of database-per-user seems to be a totally different design than people have used with traditional n-tier designs.

Good point about NoSQL! But, wasn’t part of the reason MongoDB fell out of favor because it was lacking consistency?

[gqewogpdqa]

Yeah, I think MongoDB went through a set of steps - atomically consistent at document level (which is fine for many apps as you have most related data in the single document anyways) - atomically consistent within a collection - and now, with MongoDB 4.0 and higher (released in 2017? 2018? whatever, a long time ago), MongoDB supports full transactional consistency across documents, collections, and shards. It took them awhile, but they got there.