Shape the service for its consumer

One underlying BO may serve more than one consumer. A projection layer can adapt the data shape and restrict available operations for a particular API or UI without duplicating the base business rules.

Expose a deliberate subset

projection;
use create;
use update;

This is the body of a projection behavior definition, not the complete artifact. It works with a CDS projection view and a projection BDEF that references the base behavior definition. Here, create and update are exposed; delete is not.

Projection is not a security substitute. The base BO still enforces its rules, and authorization must be designed independently. Add this layer when a consumer needs a distinct contract, not automatically for every service.

Sources

• SAP Samples: RAP projection layers
• ABAP Keyword Documentation: RAP projection behavior definitions

projection;
use create;
use update;