EF + DDD = true?

by Jimmy Nilsson

About Jimmy Nilsson

Primarily a developer and architect,

but also a trainer and author

Blog: JimmyNilsson.com/blog/Twitter: twitter.com/JimmyNilsson

Author of ”Applying Domain-Driven Design and Patterns” and ”.NET Enterprise Design”

Co-founder and CEO of factor10

Relational database?

O/RM or ”manual”?

EF or NHibernate?

EF 3.5, how to prepare for 4?

DDD and TDD!

?

Relational database?

O/RM or ”manual”?

EF or NHibernate?

EF 3.5, how to prepare for 4?

DDD and TDD!

:-)

Why TDD?

TDD isn’t about testing......it’s about programming!

To write simpler, clearer and more robust and maintainable code!

Why DDD?

Accidental complexity is bad

”Programming is understanding”(Kristen Nygaard)

”DDD == OO done right”

Context is king

Semantics over technology

...

But also with TDD and DDD we most often need to persist dataIt’s just not the main focus...

Assume that we might use a relational database

EF?

EF3.5DB-first (generate metadata and classes)IPoco

EF4DB-first (generate metadata and classes)Model-first (”paint” metadata, generate DB and classes)Code-first (”generate” metadata in runtime, generate DB)

Disclaimer

Not a review! No production experience... No analysis...

Our story can begin...

Domain expert: Lotta

Who needs a new app...TimeReport!

Developer: Jimmy

Time report

”- Show me the code!”

Recommendation

Frameworks come and go,

good design lasts! So...

Focus on DDD and TDD!

References

[DDD] Eric Evans: Domain-Driven Design[ADDDP] Jimmy Nilsson: Applying Domain-Driven Design and Patterns