Why do databases like DynamoDB and Cassandra choose AP?
They prioritize availability and latency over strong consistency. During partition, they accept writes on any replica and merge diverged copies later (eventual consistency). For workloads like advertising impressions, cache layers, or activity feeds, accepting a few seconds of stale data is worth sub-millisecond responses at 99.99 percent uptime.
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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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