- What is a ledger-style database?
This database is meant to insert operations only; there are no updates. Then, you create a view that aggregates the inserts together.
- What is CQRS?
Command Query Responsibility Segregation is a pattern that segregates the responsibilities between Query (to inserts) and Commands (to updates).
- When should you use CQRS?
CQRS can be a good pattern to apply for task-based or event-driven systems, especially when the solution is composed of multiple applications and not a single monolithic website or application. It is a pattern and not an architecture, so it should be applied in specific cases and not in all business scenarios