CAP Theorem

Summary

A theorem stating a distributed system can only guarantee two of three properties at once during a network failure: Consistency, Availability, and Partition tolerance.

• 1Explain CAP theorem in your own words with a concrete example.
• 2Classify a database you know, e.g. PostgreSQL or DynamoDB, by which two properties it prioritizes.
• 3Understand partition tolerance is essentially mandatory for any real distributed system — the real choice is C vs A.