SOA Challenges: Entity Aggregation

Ramkumar Kothandaraman has a good article just released on MSDN discussing SOA Challenges: Entity Aggregation. Aggregation is a much better name than “composable entities“ since it's definition implies that property sets of an entity grow as more child entities are merged into it. This also implies that you need a mapping layer and conflict resolution to resolve duplicate property names or just rename them for that matter.

This is becoming an important technique for passing xml documents up the stack of web services, each one adding their own value to the entity - or aggregating in a master/slave hierarchy topology. Either way, one of the subtle things about entity aggregation is that you can also think of it as a lightweight form of multiple inheritance for the properties of your domain objects. Is that useful or am I just bent?