This situation leads us to the idea of each service having its own private data. Only that service should be allowed to fetch, update, or modify that data. This can be achieved in different ways. Each microservice can have a set of tables assigned to them. Data in these particular tables can be modified by only a particular service. To implement this idea, the service can have a user defined in the database who is allowed to alter certain tables. This way, we can ensure that each service does not disturb the data in tables that are related to other microservices.

The idea of having tables in one database and having authorized access to those tables seems good, but again, it will bind us to one kind of database, such as Oracle or MySQL. If one team wants to try another kind of database for performance, they wouldn't be able to use it in this scenario.