Building Blocks of EDD

Intro

In the Introducing EDD article I introduced the simple building blocks of EDD. Also in the Heart of EDD article, I briefly described the philosophies behind it. In this article, I will show you the tools that we need to bring in our backpack for exploring a complex a domain.

Domain Concept

A significant concept within the problem space from a business perspective (e.g., “Hotel Voucher”, “Booked Room”, “Hotel Availability”, “Hotel Room Pricing”).

Domain concepts should not be a verb or an action. In fact a verb or action needs a house!. They need someone/something/somewhere to execute them. The house is a Domain Concept. For example, the action ‘transfer funds’ requires the context of ‘account’ and ‘bank,’ which are domain concepts.

Example

A concrete example is provided to clarify and evaluate each domain concept (e.g., a sample hotel voucher).

Relationship

Inherent connections exist between domain concepts within each layer of the model (e.g., the relationship between a voucher and a booked room).

Questions and Discussions

All questions and discussions are welcomed and documented to facilitate a thorough understanding (e.g., “What if a guest cancels a reservation?” “How should the cancellation policy be applied?”).

Business Rule

A business rule governs one or more domain concepts by defining a constraint or condition (e.g., checking room availability, ensuring children have a parent/guardian).

All in One Picture