How do we join the data among different microservices?
Using a Single Database Cluster (leveraging the schemas or tables) This solution is helpful when you have one single database cluster and different microservices. The idea is to give ownership of different schemas/tables to each of the services. Each service is responsible for writing its data.
Does each Microservice need its own database?
The short answer is yes. In order to be able to independently develop microservices , they must be loosely coupled. Each microservice’s persistent data must be private to that service and only accessible via it’s API .
What kind of database do I need for microservices?
Other services might need a NoSQL database such as MongoDB, which is good at storing complex, unstructured data, or Neo4J, which is designed to efficiently store and query graph data. Use a (single) database that is shared by multiple services. Each service freely accesses data owned by other services using local ACID transactions.
How is a database shared by multiple services?
Use a (single) database that is shared by multiple services. Each service freely accesses data owned by other services using local ACID transactions. The OrderService and CustomerService freely access each other’s tables.
What to know about query side in microservices?
The query-side modules implement queries and keep the data model synchronized with the command-side data model. And as for the command side modules, they manage the operations. You can apply CQRS within a service and use it to define query services. A query service’s API consists of query operations only.
When do you query data owned by multiple services?
Some business transactions need to query data that is owned by multiple services. For example, the View Available Credit use must query the Customer to find the creditLimit and Orders to calculate the total amount of the open orders. Some queries must join data that is owned by multiple services.