Questions tagged [read-model]
The read-model tag has no summary.
23 questions
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How to load consistent test data into multiple applications (which communicate by message streams)?
I have a system landscape consisting of multiple applications.
Each application provides REST interfaces to communicate with the outside world.
Each application has its own data storage (some kind of ...
- 207
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Reducing the code duplication between read and write application in CQRS
I am building an application and trying to embrace Domain Driven design principles, CQRS and event sourcing.
We are having two applications one for reading and another for writing. The write ...
- 1,464
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ES/CQRS: How to access additional information in projections
I'm developing an event-sourced/CQRS application and do not understand the best strategy to use when building the read model projections when additional domain data is needed. A partial representation ...
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get aggregate id based on its data in it
I have an aggregate root called SizeRangeAggregate which holds the range of size of clothing piece dimension and price for that range.
I created an post rest API which create new SizeRangeAggregate. ...
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DTO vs. read model
If I understand the concept of read models correctly, then it's just a simple query to return a use case specific data set.
But a DTO seems to have the same purpose, but in a more complex way (...
- 572
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Event Sourcing - Reconstituting Aggregate from Wrong Event Stream
I am working on a project to help learn DDD and am trying to do CQRS and Event Sourcing. Code is in C#.
For this example, lets say I have 2 aggregates, Customer and Product. My aggregate repository ...
- 338
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CQRS-Event Sourcing: how to process events in the expected order inside the read model
I'm looking for some insights about how to handle the read model in a CQRS Event Sourcing application, in order to do the best to ensure data consistency.
The missing point is how to be sure (...
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CQRS, What reasons cause read model update delay? How to prevent user from taking inconsistence data?
I am considering CQRS for building a realtime game server (not gameplay but the economy).
For some reasons. Scaling, Event logging, Model changing.
However in realtime game when player upgrade, for ...
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Does CQRS need to be fire and forget, If we need to read guarantee after command?
I'm in researching phase of CQRS+ES. Never done in real world yet. But very soon.
However what I saw in StackOverflow and projects, CQRS seems to be fire and forget.
So what if there is a chain ...
- 717
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CQRS and microservices: passing information from one service to another
We're building two microservices that use CQRS and Event Sourcing: an Order Service and an Inventory Service. When an order is made, the inventory of that item must be decreased by the amount ordered. ...
- 988
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Rehydrating Aggregates from a "snapshots" projection rather than the Event Store
So I've been flirting with Event Sourcing and CQRS for a while now, though I've never had the opportunity to apply the patterns on a real project.
I understand the benefits of separating your read ...
- 11.6k
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DDD - Same ID/Primary Key, different Aggragate Root class per Bounded Context
I am working on understanding DDD and want to see if this idea is sound, if it is common practice, and if there are any pitfalls or unforeseen complications.
I want to effectively have one "entity" ...
- 338
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4k
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How do event sourced systems make sure the read model is only updated once?
Currently looking into Event Sourcing in a Microservices architecture and I've found this article. It describes a possible implementation of CQRS and event sourcing.
If the logic dealing with updating ...
- 151
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CQRS + Event sourcing - event groups and event propagation
This is my current CQRS use-case setup:
Command DTO is received in application layer handler where we map Command DTO to appropriate domain objects if needed, re-hydrate aggregate root from repo and ...
- 367
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CQRS without DDD and without (or with?) ES - what is write model and what is read model?
As far as I understand, the big idea behind CQRS is having 2 different data models for handling commands and queries. These are called "write model" and "read model".
Let's consider an example of ...
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