What is the importance of database per service in microservices, and what are the challenges?

Importance:

• Decoupling: Each microservice manages its own data, avoiding shared database

bottlenecks and promoting service independence.

• Scalability: Independent databases allow microservices to scale individually based

on load.

• Flexibility: Services can choose different types of databases (SQL, NoSQL) based

on their needs (e.g., relational data for one service, document store for another).

• Autonomy: Microservices can evolve independently without impacting others, as

database changes in one service don’t affect others.

Challenges:

• Data Consistency: Ensuring consistency across distributed databases is complex.

Eventual consistency and patterns like Sagas need to be used.

• Data Duplication: Some data might need to be duplicated across services, which

can lead to synchronization challenges.

• Complexity: Managing multiple databases increases operational complexity, such as

database migrations and monitoring.