Agreed overall, see my comment above which addresses this. These types of systems typically will never see as many transactions/sec as their “likes” counterparts, for obvious reasons.

Having said that, I have worked on some credit card infrastructure that does get up there, and it too, does not have FKs. Having or not having FKs does not magically mean your data will be accurate or in-accurate. ACID, as well as traditional database transactions, still apply, and keep your data integrity high. In conjunction with well designed application logic, and proper planning, FKs are not needed to maintain accurate data whatsoever.

Also, there is commerce related things (Amazon) that work on truly eventually consistent data stores, like DynamoDB. Don’t see amazon getting laughed at much. (they use it for their shopping cart, source: http://www.allthingsdistributed.com/2007/10/amazons_dynamo.h... , this paper is also a great read fwiw)

Anyways, I think we are getting a bit into the weeds here, as the OPs link is about a mysql bug. Cheers.