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Repositories or Command/Query Objects? What about CQRS? Unit of Work?

From time to time, when I learn something new or want to try out a new approach, I restart my "Record Collector" a project. It is a project I use for testing out ideas, and never gets close to a usable product.

This time I wanted to try out creating components and setting up the relationship between them using inspiration from Clean Architecture. The Record Collector application keeps track of different records, and needs some sort of record repository.

For my simple application is it enough to just have an in-memory list. But I got curious I wanted to see how larger applications, maybe targeting thousands of simultaneous users, tackles this.

What I found was the Repository Pattern and CQRS.

Here is some resources for any of you who wants to know how repositories or command/query objects can be implemented in large scale applications:

The Repository Pattern (msdn)
Youtube video by Mosh Hamedani explaining the Repository Pattern
Blogpost discussing Repositorios vs Command/Query Objects
CQRS explained by Microsoft

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