DDD - what to be guided by when referring a method to an entity?

Question

Problem-Based Design

Good afternoon!
There is an entity Client, there is an entity Account.
To which entity should the GetClientIdByAccountNumber method be attributed?

Answer 1

There is no need to have such methods at all. We receive the client, we receive its identifier. At the DDD level, we operate with domain entities, and the method that you want can only apply to an abstract service in a vacuum, which will be built on top of the domain model