How to design microservice database one to many?

Question

i have a question about microservices and database design. Situation: I have a Service AircraftsService which handle all data about an aircraft, an aircraft type and so on. And i have a Service FlightsService which handle all data about flights. I have to link the aircraft to a flight. Normaly i would create a foreign key in the flights table that links the aircraft. But in microservice architecture i understand that i have domains and seperate databases. So my question is how can i represent this problem.

My first thought was that i have a database for all aircrafts and a database for all flights. the flights table becoms a 'indirect' foreign key to the aircraft. When i call the flight service the flight service call the aircraft service with the id from the flight table, then build the response. That promised that i do not call the aircraft database direct from the flight service.

Is my solution correct? What is the best practice in this use case?

After i thought about the problem, what is when i delete an aircraft i have to tell the flight service that an specified aircraft not exist any more and the flight service have to update the 'indirect' foreign key.

Can somebody help me?

Thanks

Answer 1

There are various ways of best database practices when dealing in micro services , it may differ with respect to domain of the entities which are being used , and also the scope of your application use.

There are few best practices for database design in micor services , to start with listing few of them

1 - Private-tables-per-service – each service owns a set of tables that must only be accessed by that service
2 - Schema-per-service – each service has a database schema that’s private to that service
3 - Database-server-per-service – each service has it’s own database server.

You can mix and match these are per your data size and data count.

I would like you to refer and go through this page for a perfect example.

Microservices Database Best practices

Identify the load on each service that you will have. Load can be counted in 2 ways.

• Data load (how much data will be retrived)
• Service hit count (how many times service will be called)

Then you can decide the appraoch.