DomainDriven Design for the DatabaseDriven Mind Julie Lerman

Domain-Driven Design for the Database-Driven Mind Julie Lerman the. Data. Farm. com @julielerman

My Courses on Getting Started with EF 6 Domain-Driven Design Fundamentals Looking Ahead to Entity Framework 7 EF 6 Ninja Edition: What’s New in EF 6 Automated Testing for Fraidy Cats Like Me Getting Started with Entity Framework 5 Entity Framework in the Enterprise Entity Framework Code First Migrations Data Layer Validation with Entity Framework 4. 1+ Entity Framework 4. 1 - Db. Context Data Access Entity Framework 4. 1 - Code First Querying the Entity Framework Designer Supported EDM Customization Entity Framework and Data Models Entity Framework 4. 0 By Example © DEVintersection. All rights reserved. http: //www. DEVintersection. com

Your Workflow? © DEVintersection. All rights reserved. http: //www. DEVintersection. com

database domain © DEVintersection. All rights reserved. http: //www. DEVintersection. com

Forget persistence? What about shared data & types? How will DDD patterns resolve with

Value of Domain-Driven Design Patterns for Implementing Persistence for DDD © DEVintersection. All rights

Business Problem © DEVintersection. All rights reserved. http: //www. DEVintersection. com

Data Storage is not the Business Problem © DEVintersection. All rights reserved. http: //www.

Cross-Cutting Concerns © DEVintersection. All rights reserved. http: //www. DEVintersection. com

DDD Thinking: Divide and Conquer © DEVintersection. All rights reserved. http: //www. DEVintersection. com

Each Bounded Context public class Customer{ “Customer” “A Customer Registers” private Customer (string Name, Date reg. Date){} public static Create Register (string Name, Date reg. Date){ return new Customer(name, reg. Date); } © DEVintersection. All rights reserved. http: //www. DEVintersection. com

Domain-Driven Design Thinking © DEVintersection. All rights reserved. http: //www. DEVintersection. com

Entities: More than data containers Anemic Type for CRUD public class Patient { public int Id { get; set; } public Client Pet. Owner { get; set; } public int Client. Id { get; set; } public string Name { get; set; } public Gender { get; set; } public int? Doctor. Id { get; set; } } Rich Domain Model for DDD private © DEVintersection. All rights reserved. http: //www. DEVintersection. com

No Shared Data? No Shared Types? PANIC © DEVintersection. All rights reserved. http: //www.

Data Sharing Patterns & Anti-Patterns Bad (No-Op) Good* Better Best Even Better than Best

Anti-Corruption Layer Not Just for Connecting Apps © DEVintersection. All rights reserved. http: //www.

When to Share Types § Shared Kernel o o o Tightly coordinated Entities and Value Objects Common schema and behavior “Reduce duplication, but not eliminate it” (Eric Evans, DDD book) § Inheritance o o o Infrastructure Not domain types Favor composition over inheritance © DEVintersection. All rights reserved. http: //www. DEVintersection. com

Domain Model and Persistence Model Domain Model Aggregate Root ORM DB Entities Value Objects

Domain as Persistence Model Domain Model Aggregate Root Entities Value Objects Entity Framework API,

Yes You Can © DEVintersection. All rights reserved. http: //www. DEVintersection. com

Code Sample for this session is at github. com/julielerman/Domain. Driven. Designfor. Database. Driven. Mind

Resources MY STUFF: Domain-Driven Design Fundamentals on Pluralsight bit. ly/PS-DDD All of my Pluralsight courses: pluralsight. com/author/julie-lerman A Pattern for Sharing Data Across DDD Bounded Contexts (Part 1&2) MSDN Magazine, Oct & Dec 2014: bit. ly/Data. Points_Dec 2014 Entity Framework Model Partitioning in Domain-Driven Design Bounded Contexts Tech. Ed Europe 2014: bit. ly/TEE 2014_EFDDD Coding for Domain-Driven Design: Tips for Data-Focused Devs (3 Parts) MSDN Magazine, Aug, Sept & Oct 2013 bit. ly/15 x. Ml. DL BOOKS: Domain-Driven Design, Eric Evans amzn. to/1 ksti. Rg Implementing Domain-Driven Design, Vaughn Vernon amzn. to/1 dg. YRY 3 Domain Modeling with Entity Framework Scorecard, Jimmy Bogard, bit. ly/1 x 925 bu CQRS Journey from MS Patterns & Practices: bit. ly/cqrsjourney © DEVintersection. All rights reserved. http: //www. DEVintersection. com