[bergkvist]

No amount of abstraction is going to save you from the problem of 2 processes manipulating the same state machine.

[pc86]

In this example, it's the job of the "database access layer service" to manage those processes and prevent issues.

But, terrible service name aside, this is a big reason why two services accessing the same database is a capital-H Huge anti-pattern, and really screams "using this project to learn how to do microservices."