Torsdagen den 12-April kör vi en CQRS-kväll i Helsingborg med Jonathan
Worthington och Carl Mäsak från Edument AB.
Det blir föreläsningar, öl och en helkväll med härliga människor.
Mer information och anmälan http://www.meetup.com/SoftPub/events/56201892/
The Pain of Relational Dominance
By Jonathan Worthington
We all know the drill. Design a database. Write code against it, maybe
helped along by some ORM. As the system grows, add more tables to the
database... And where does it lead us? All too often, to databases
with hundreds of tables, monolithic applications, and all sorts of
It's not that relational databases are bad per se; they're just
somewhat overused, and widely misused. In this talk, I'll pick apart
the causes of some of the pain this can lead to. I'll discuss why
using events can help to free us from this situation, and lead to some
powerful unifications. Along the way, I'll also show how the CQRS
architectural pattern fits in to the picture.
Giving your saga a happy ending
By Carl Mäsak
A saga, traditionally, is a story, a heroic tale, or telling of
events. The word comes from old Norse and originally meant "what is
In a message-based setting, a saga is a message handler. It can help
uphold inter-aggregate consistency, or mediate between bounded
contexts. Sagas absorb much of the complexity that was previously
encoded in the domain model as foreign keys and immediate consistency
— which often led to rigid, unmanageable systems.
As sagas grow in size and complexity, however, they themselves need
external management. This is the point where sagas show their real
strength: we get to analyze and improve the business workflow on the
story level. Business concerns live directly in the code.
In this talk, Carl Mäsak shows how to build sagas from scratch, how
they fit in a message-based application, how they can be used to
highlight business workflows, and how to manage complex sagas.