Understanding CDS View Entities vs. Root View Entities in ABAP RAP

📌 Understanding CDS View Entities vs. Root View Entities in ABAP RAP

When working with SAP ABAP RESTful Application Programming (RAP) Model, it’s essential to distinguish between View Entities and Root View Entities. 

Here’s a concise breakdown:

General View Entity:

🔹 Defines data structures, often combining data from multiple sources.

🔹 Ideal for simple data retrieval or creating intermediate views.

🔹 Defined using DEFINE VIEW ENTITY.

Root View Entity:

🔹 Serves as the top-level entry point in a RAP business object.

🔹 Defines the main data and links to related child entities.

🔹 Defined with DEFINE ROOT VIEW ENTITY.

Example:

💡 Sales Order in RAP:

View Entity: Retrieves specific sales order item details (e.g., item number, quantity, price).

Root View Entity: Represents the entire sales order, containing primary sales order information and associations to child entities like "SalesOrderItem".

Key Takeaway:

Use General View Entities for flexible data retrieval and Root View Entities to define and organize your business object hierarchy.