We are using a bunch of separate classes suffixed with `-repository` to retrieve the data from the database; for each table its own repository. We have for instance a `customerrepository` class which has all kind of methods to retrieve customers, and a `vacancyrepository` which has all kind of methods to retrieve vacancies. I have two questions about this way of doing things: 1. How about getting data which spans multiple tables? For instance I have a screen which shows all customers who have not yet created a vacancy. Can a `customerrepository` use methods from the `vacancyrespository`, or do both repositories return results and is there a class higher in the hierarchy (let's name it a `dataservice`) which gets the results from both repositories and combine them into 1 result? 2. how much logic can such a repository handle? I think it's OK to implement the 'where active == true' in a repository to retrieve only active records, or should even that simple logic be handled by a class higher in the hierarchy (let's name it a `dataservice`)? The example I was running into now is this one: We have a questions list, which contains one or more questions. The question can have a result, which is hold in a separate table. So when you want to retrieve the total result of the questions list, you have to combine data from the `questionlist` table, the question table and the `questionstatus` table. Right now we have 3 different repositories for these tables. If I would ask the `questionlistrepository` what it's the total result for list number 12, it would have to get data from two other repositories and hence have some logic in it, is that allowed? Or is there a `questionlistdataservice` which knows which repositories to use? One more thing: our repositories can result an `IQueryable` so a calling service can easily combine the results, but how about when this isn't the case, I don't think it's a good idea to retrieve all the content of all three tables from the database.