What are the three terms in databases and data warehouses: consistency, availability, and partition tolerance?

The CAP theorem states that in a distributed system, you can only guarantee two of the following three properties at any given time: Consistency (all nodes see the same data simultaneously), Availability (every request receives a response, even if it is not the most recent data), and Partition Tolerance (the system continues to operate despite network partitions). In practice, most distributed databases choose a trade‑off: for example, a strongly consistent database like PostgreSQL sacrifices some availability during partitions, while a highly available NoSQL store like Cassandra prioritizes availability and partitions, offering eventual consistency. Understanding CAP helps architects design systems that meet application requirements by selecting the appropriate consistency model and handling network failures gracefully.