Architecture

Interface

• How users interact with the database

• Includes all CRUD operations

• Can do other stuff

Execution

• Controlled by the interface

• Commands are optimised

• It manages the transactions

• Also manipulates data sent back from storage

Storage

• Stores the data

C.A.P Theorem

Distributed systems cannot be all three:

• Consistency means that all nodes in a distributed system view the same data at the same time, ensuring a single up-to-date copy of the data. (cant be available if selected)

• Availability ensures that all requests receive a response, whether it's success or failure.

• Partition tolerance means that the system will continue to operate even if there are network failures causing some of the nodes to be isolated.

According to the theorem, it is impossible for a distributed data store to simultaneously provide more than two of these guarantees. That means, in the event of a network partition, one has to choose between consistency and availability.