Event Store vs RethinkDB: What are the differences?

Introduction: Event Store and RethinkDB are both popular databases, but they have key differences that set them apart.

1. Data Model: Event Store is an event sourcing database where data is stored as a series of state-changing events, while RethinkDB uses a JSON document model similar to MongoDB. This means that Event Store provides a full audit trail of data changes, making it suitable for systems that require high traceability, whereas RethinkDB is more flexible in its data structure but may not offer the same level of historical data tracking.

2. Query Language: RethinkDB uses ReQL, a powerful and flexible query language that allows users to perform complex queries with ease. On the other hand, Event Store relies more on projections and subscriptions to query data, which can be a bit more challenging for users unfamiliar with this approach. This means that RethinkDB may be more suitable for developers who prefer a traditional query language, while Event Store may be better for those who value event-driven architectures.

3. Scalability: While both databases support horizontal scaling, Event Store has a specific focus on high-performance event-driven systems and is optimized for handling large volumes of events. RethinkDB, on the other hand, may not be as optimized for event-driven workloads and may have limitations in scaling for certain use cases. This means that Event Store may be a better choice for applications that require high scalability and performance.

4. Community and Support: RethinkDB has a larger community and more extensive documentation compared to Event Store, making it easier for users to find resources and get help when needed. Event Store, however, is backed by a company and may offer more direct support options for enterprise users. Depending on the level of support and community engagement required, users may choose one over the other.

5. Use Cases: Event Store is well-suited for applications that require event sourcing, CQRS (Command Query Responsibility Segregation), and event-driven architectures. On the other hand, RethinkDB is suitable for real-time applications, IoT (Internet of Things) projects, and data analysis tasks. Depending on the specific use case and requirements, users may choose either database for their project.

6. Data Durability: Event Store prioritizes data durability by ensuring that events are stored in an append-only manner and can only be appended to the event log. This guarantees that events are never lost or overwritten, providing a high level of data consistency. RethinkDB, on the other hand, may offer eventual consistency in some cases, which means that data updates may not be immediately reflected across all nodes in the cluster. This difference in data durability may impact the choice of database depending on the application's requirements.

In Summary, Event Store and RethinkDB differ in their data models, query languages, scalability, community support, use cases, and data durability, making each database suitable for different types of applications and architectures.