CAP theorem. You can't have guarantee for having all three all the time. But you can still have nice thing most of the time.

Even better, sometimes you can change which guarantee you need.

We can do better then "pick two"

yes, but no. because in reality what we really want is not true pure AP or CP (or CA, which you can't have anyway)

https://www.youtube.com/watch?v=hUd_9FENShA

(CAP is a very important result about a very strong assumption of consistency: linearizable events, but for that you can't lose any messages [if I remember it correctly], otherwise the system will become inconsistent)

Thanks for the video, very interesting.

I've always found CAP theorem to be better described as:

Given the need for Partitions, you must choose between prioritizing Consistency or Availability.

Google Spanner does the three.

> The purist answer is “no” because partitions can happen and in fact have happened at Google, and during some partitions, Spanner chooses C and forfeits A. It is technically a CP system.

— https://cloud.google.com/blog/products/databases/inside-clou...