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CAP Theorem Tutorial Series - What is Availability?

In this episode of the Cockroach Hour our host, Jim Walker, continues his journey through the CAP Theorem and explains what Availability is and how it affects your deployments. The CAP Theorem states that it is impossible for a distributed database to simultaneously guarantee more than two of the following: Consistency, Availability, or Partition Tolerance. The widely accepted theorem is often used to analyze and position new databases. In this series, we explore the three guarantees, delivering a definition for each, and outlining how each might affect your database implementation. This is a rather academic series of talks and hopefully, we will help you understand the tradeoff for each. In this session, we explore availability, which states that ”every request receives a (non-error) response, without the guarantee that it contains the most recent write”. We cover: What are the availability challenges for a distributed database. Why is availability important and what workloads is it important for. What is the effect of availability potentially returning incorrect data. How CockroachDB delivers some key traits for availability.