1. Investigating CQRS Mark J. Miller http://www.developmentalmadness.com

2. Overview Introducing CQRS Investigating SimpleCQRS framework Extending SimpleCQRS – Adding IoC – Replacing “storage” (Event Sourcing, Read Model) – Client Ids – Optimizing Serialization – Guaranteed Delivery – Event Store transparency (how do I look at the data?)

3. Introducing CQRS Impedance Mismatch Command-Query Responsibility Segregation CQRS != Event Sourcing Eventual Consistency not required (but it helps) Idempotence and Guaranteed Delivery (At-least once) Very DDD friendly – (Read the book)

4. Command/Query Responsibility Segregation QueriesQueries CommandsCommands DB WSWS InputInput ValidationValidation ValidationValidation RulesRules QueriesQueries View Model Updater Updater Publish UI

5. Demo SimpleCQRS Gui

6. SimpleCQRS

7. SimpleCQRS Process Flow

8. Extending SimpleCQRS – Adding IoC – Replacing “storage” (Event Sourcing, Read Model) – Client Ids – Optimizing Serialization – Guaranteed Delivery – Event Store transparency (how do I look at the data?)

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12. Comb?

13. CQRS Samples SimpleCQRS – Greg Young – http://github.com/gregoryyoung/m-r http://github.com/gregoryyoung/m-r Fohjin.DDD – Mark Nijhof – http://github.com/MarkNijhof/Fohjin/tree/master /Fohjin.DDD.Example/ http://github.com/MarkNijhof/Fohjin/tree/master /Fohjin.DDD.Example/ CQRS Kitchen – Dennis Doomen – http://thecqrskitchen.codeplex.com/ http://thecqrskitchen.codeplex.com/

14. Did you mean CARS? CQRSInfo.com http://groups.google.com/group/dddcqrs Greg Young - codebetter.com/blogs/gregyoung Udi Dahan – www.udidahan.com Mark Nijhof - elegantcode.com Jonathan Oliver - jonathan-oliver.blogspot.com DDD: – Domain-Driven Design, Eric Evans – http://www.infoq.com/minibooks/domain-driven-design-quickly http://www.infoq.com/minibooks/domain-driven-design-quickly Comb: – http://www.informit.com/articles/article.aspx?p=25862&seqNum=7 http://www.informit.com/articles/article.aspx?p=25862&seqNum=7 – http://sqlblog.com/blogs/alberto_ferrari/archive/2007/08/31/how-are-guids-sorted-by-sql- server.aspx http://sqlblog.com/blogs/alberto_ferrari/archive/2007/08/31/how-are-guids-sorted-by-sql- server.aspx