What does consistency mean in CAP?
Consistency (in CAP) means linearizability: every read reflects all writes that completed before it. If you write v=99 and the write succeeds, the next read sees v=99. Under partition, achieving this requires quorum: refuse the write if you can't reach a majority of replicas. Weak consistency (eventual consistency) relaxes this and allows temporary divergence.
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The CAP Theorem Is Not a MenuNetwork partitions force a hard choice: refuse writes (CP) or accept and diverge (AP). Why the two-of-three myth is wrong, and what PACELC really tells us.
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