Description

The RAP behavior definition header of an abstract BDEF can define the attributes listed below. The implementation type is mandatory; strict[(version)] and with hierarchy are strongly recommended for the following reasons: strict mode ensures that no outdated syntax can be used. When leaving out with hierarchy, the abstract BDEF represents the same BDEF derived type as a single CDS abstract entity and does not offer any additional value.

• abstract: An abstract BDEF must have the implementation type abstract.
• strict[(version)]: It is strongly recommended that the most recent version of BDEF strict mode is used.
• extensible: If specified, BDEF extensions are allowed. As a prerequisite, BDEF strict mode must be switched on using the keyword extensible. For more details, see the topic RAP - extensible.
• with hierarchy [like entity]:
• The optional addition with hierarchy causes the construction of a new kind of BDEF derived type for the entities that are part of the BDEF: starting from the RAP BO root entity, such a type contains all entity fields, plus a component for each CDS composition. For a composition with a unique target cardinality, i.e. TO ONE or TO EXACT ONE, this component is a structure; otherwise, the component is a table. The type of the component (or its line type) is defined recursively in the same way, down to the leaf level in the CDS composition hierarchy.
• The addition like entity can optionally be used in combination with with hierarchy. It guarantees that the hierarchical BDEF derived type that is constructed from the abstract BDEF is equivalent to the underlying CDS type that is derived from the abstract entity. The addition with hierarchy like entity enforces the following additional syntax rules:
• - The abstract BDEF in question must not contain any CDS compositions in its BDEF derived type.
• - The field attribute suppress is not allowed, as this would create a difference in BDEF derived types between the underlying abstract entity and the abstract BDEF.
• - The field attribute mandatory:execute is not allowed.
• - The optional addition with control is not allowed.

The behavior definition header is followed by an entity behavior definition.