Difficult business logic - CQRS forces you to avoid mixing domain logic and infrastructural operations. Scalability matters - With CQRS you can achieve great read and write performance, command handling can be scaled out on multiple nodes and as queries are read-only operations they can be optimized to do fast read operations.

2012年5月23日 · If you are using CQRS, then probably you will have a repository that looks somewhat like this. public interface IRepository<T> where T : AggregateRoot, new() { void Save(AggregateRoot aggregate, int expectedVersion); T GetById(Guid id); T GetById(Guid id, int version); } Hope this helps Cheers

2015年5月2日 · The important thing is that you separate your write and read models in classic CQRS style. That does not mean that you cannot do a read in the same request as you do the command. Sure, you can send a command to the server and then with SignalR (or something) wait for a notification that your projection have been created/updated.

2017年5月24日 · I am building HTTP REST API and implementing CQRS, DDD, ES, and microservices concept for the API. Cool. Keep firmly in your mind that the REST API part is part of your integration component; its purpose is to ensure that old clients can continue to take advantage of your services, even as the implementation of those services evolves.

2018年8月21日 · In CQRS the write persistence and the read persistence are separate (logically, temporally and even physically) and what you are experiencing is normal, you should embrace this and not see it as a fundamental problem. Instead you should modify your client to compensate for this.

2016年10月16日 · It's a bad practice, because such way ignores two main advantages of CQRS. First is simple code support and clear structure, because you have separated business logic and queries (aggregated data for visualization). Second advantage is in scaling. One instance handles commands, and another 5 processes requests.

2018年2月7日 · However, it appears as though you are using data-oriented classes (perhaps entity framework). Your domain model would typically map from any data storage mechanism (even an ORM, unless your ORM has the ability to use the domain model directly). I try to avoid ORMs. The next thing is that CQRS isn't really in the picture yet. This also doesn't ...

For Event store I recommend superior Postgresql extension called TimescaleDB, which focuses on high performance timeseries data processing (events are timeseries) in large volume. Of course CQRS, Event sourcing (replay, etc. features) are built in light4j framework out of the box which uses Postgres as low storage.

2012年4月7日 · However, when looking at CQRS, the query would not hit the same repository. Instead, it would perhaps go directly against the data store and always be denormalized. And my command side would evolve to a NewRunCommand and Handler that would create and populate a NewRun domain object then persist the information to the data store.

2017年4月16日 · CQRS and CQS are like microservices and class decomposition: the main idea is the same ("tend to small cohesive modules"), but they lie on different semantic levels. The point of CQRS is to make write/read models separation; such low-level details like return value from specific method is completely irrelevant.