[marcosdumay]

While the problem on the article is less of an issue in Postgres (the indexing cache locality is still there), they are still slower than the serial ones.

I don't know if you save enough problems by using them as alternative keys in Postgres for it to be faster, my guess is that just using them as primary key would be faster than a serial primary key and an UUID alternative one. Still, UUIDs are much more useful as client-facing data than as a pure database value, so I would also do that (and standardize my PK format), probably paying a performance penalty.

[cbsmith]

"Slower" is a matter of context. Like with most things, there are trade offs to allow for more concurrency. UUIDs are intended to avoid serialization with ID generation, which makes sense in a federated system. Yes, they take up more space and aren't all neatly ordered, but the trade off works out well for the right kind of systems (FlakeIDs are a better trade off for more contexts). The problem this article is describing is you're getting the worst of both worlds, because you're still serializing in the MySQL database...