Microservice pattern: Shared database

Description:
The Microservices - Shared Database design pattern involves multiple microservices sharing a single database schema. This pattern can be used to manage distributed data transactions and maintain data consistency across different microservices.

Main elements of the pattern:

• Shared Database: A single database is shared among multiple microservices.
• Data Consistency: Ensuring data consistency and integrity across microservices.
• Transaction Management: Handling distributed transactions efficiently.
• Service Independence: Maintaining the autonomy of each microservice while sharing a common data source.
• Database Schema Design: Careful design of the database schema to avoid tight coupling between microservices.
• Security: Implementing robust security measures to protect the shared data.
• Scalability: Ensuring that the shared database can handle the load from multiple microservices.

References:

1. Project Contribution Guidelines
2. Microservices Architecture Patterns - Microservices.io
3. "Building Microservices" by Sam Newman
4. Martin Fowler's Blog on Microservices
5. Spring Cloud Documentation

Acceptance Criteria:

1. Create a new package for the Microservices - Shared Database design pattern within the project.
2. Implement a working example demonstrating the shared database pattern with at least two microservices.
3. Ensure that the example includes:
   • A shared database schema
   • Transaction management across microservices
   • Data consistency mechanisms
4. Include unit tests and integration tests to validate the functionality.
5. Provide comprehensive documentation explaining the implementation, including code comments and a README file in the package.
6. Ensure the implementation adheres to the project's contribution guidelines and coding standards.

Start by reviewing the project contribution guidelines and the referenced Microservices.io, Building Microservices, Martin Fowler, and Spring Cloud materials. Then inspect the repository's existing Java design-pattern examples to determine the appropriate package structure; done means a documented shared-database example with at least two microservices, tests, schema, transaction and consistency coverage, and a README.