Data Consistency Properties and the Trade-Offs in Commercial Cloud Storages: The Consumers' Perspective
A new class of data storage systems, called NoSQL (Not only SQL), has emerged to complement traditional database systems, with rejection of general ACID transactions as one common feature. Different platforms, and indeed different primitives within one NoSQL platform, can offer various consistency properties, from Eventual Consistency to single-entity ACID. For the platform provider, weaker consistency should allow better availability, lower latency, and other benefits. This paper investigates what consumers observe of the consistency and performance properties of various offerings.