Working with massively distributed database systems

The CAP Theorem and Architectual Consequences

Martin Schoenert

The blunt formulation of the CAP theorem states that any database system can achieve only 2 of the 3 properties: consistency, availability and partition-tolerance. We look at it more closely and see that this
formulation is misleading, because there is not a single big design decision but several smaller ones for the design of a database system. We then concentrate on the architectural consequences for massively
distributed database systems and argue that such systems must place restrictions on consistency and functionality.