Domain Driven Design Entity Vs Value Object

Entities when two objects are deemed equal on the basis of their identity they are considered entities.

Domain driven design entity vs value object. The topic described in this article is a part of my domain driven design in practice pluralsight course. A value object is fully identified by a combination of values it contains. That is unlike an entity which has a unique identifier and remains distinct even if its properties are otherwise identical two value objects with the exact same properties can be considered equal. I wrote about entities and value objects some time ago.

So what we have in this example is an aggregate consisting of a single entity the purchase order functioning as the root of the aggregate and a set of one or more associated line item value objects. A value object represents an aspect. The only way your code determines. An entity object on the other hand has its own life and rich behavior regardless of the data it contains.

In this post i d like to talk about differences between entity vs value object in more detail. And make the po entity the root of the aggregate. Suppose you have two employee objects in your system i e. Entities vs value objects in domain driven design in today s blog post we will be discussing the differences between entities and value objects in domain driven design.

Using a table for each type of value object a design that allows. The difference between entities and value objects is an important concept in domain driven design. Value objects are a pattern first described in evans domain driven design book and further explained in smith and lerman s domain driven design fundamentals course. Inline value objects fields in the entity table a simple design that also supports refactoring of value objects from an entity.

So treat po as an aggregate of the po entiity and the line item value objects. A value object class represents an entity in the domain that mostly contains data and lives for the data it contains.