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Please stop calling databases CP or AP

martin.kleppmann.com Essays & writing Essays & articles Computer science Candidate
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Resurfaced independently across 5 calendar years, with breakout response in 2 of them.

submissions
7
submitters
7
observed span
2015–2025
peak thread · 51 comments
200 pts
latest 20+ return · 2020-09-07
151 pts

Submission timeline

2007–2026

One slot for every year since HN launched. Height is that year's peak points; orange marks a 100+ point or 50+ comment breakout. Select a bar to open its strongest thread.

First comments on top threads

HN comment order

The article convinced me that talking about databases as CP or AP is not very useful. The article did not convince me that CAP-centered thinking is itself harmful or counterproductive. It's true that C-Consistency and A-Availability are relatively blunt definitions in a landscape of diverse and subtle possible semantics. But their usefulness is that they represent our intuitive notions of what a database should do. If it were possible and had good performance, every single database system would provide C…

Martin Kleppmann applies critical thinking to the claims of NoSQL marketing; I wish I was aware of his work at the time. I always found it frustrating that the semantics of the word "Consistent" in ACID has nothing to do with the semantics of CAP "Consistency". ACID Consistency refers to integrity constraints while CAP Consistency seems to refer to Cache Coherence across nodes in a cluster. I was a little surprised that Kleppmann uses the idea of "Linearizability" to explain…

sradman·151-point thread·

The first top-level comment from each of the four biggest threads, in HN’s own order. Excerpts are shortened; open a comment for full context.

Breakout years
2

100+ points or 50+ comments

Total points
358

reference only — not used in Hall rules or ranking

Total comments
85

reference only — not used in Hall rules or ranking

Every submission

DateTitle as submittedByPointsComments
2015-05-11Please stop calling databases CP or APFirst breakout · Best threadmartinkl20034
2017-01-20Please stop calling databases CP or AP (2015)bsg7510
2017-06-28Please stop calling databases CP or APflying_whale10
2020-09-07Please stop calling databases CP or AP (2015)Latest 20+ point returnreese_john15151
2024-05-13Please stop calling databases CP or AP (2015)Tomte10
2025-04-11Please stop calling databases CP or APfanf220
2025-05-16Please stop calling databases CP or APStefanBatory20