This chapter mainly focuses on the trade-offs in different data architectures.

Terminology

Three important concerns

1. Reliability: The ability of a system to continue to work correctly even when facing failures(hardware, software or human errors).
2. Scalability: As the system grows(data, traffic, complexity), the system must be able to handle the load.
3. Maintainability: The ability of a system to be change in future.

Operational system : Operational means it always modifies data in the database; therefore, it performs data transactions. This kind of system is used by backend businesses and software engineers. For example: bank systems, booking systems, etc Analytical system: Analytical means it is related to data analysis; therefore, it uses a read-only copy from the operational system to perform statistics. This kind of system is used by business analysts (to make future decisions) and data scientist For example: supermarket goods analysis system, stock market or