juniorCAP Theorem
Explain Consistency in the context of CAP.
Updated Apr 28, 2026
Short answer
Every read receives the most recent write or an error.
Deep explanation
The CAP Theorem is a fundamental principle in distributed systems design. Every read receives the most recent write or an error. It forces architects to acknowledge that trade-offs are unavoidable in wide-area networks.
Real-world example
A single-node relational database behaves as CA until it scales horizontally.
Common mistakes
- Thinking CAP applies to systems that aren't distributed (like a single-instance DB).
Follow-up questions
- Is CAP relevant for single-core apps?