C0 Contract Rules for Consumers of DDIC Objects

ABAP - Keyword Documentation → ABAP - Rules for ABAP Cloud → Contract Rules for ABAP Released APIs → C0 Contract Rules → C0 Contract Rules for DDIC Objects →

Mail Feedback

The provider rules for objects with the C0 contract ensure that released objects are changed only in a very restricted way and help to avoid errors and interruptions after an SAP upgrade. Nevertheless, the rules do not prescribe full downward compatibility and leave some room for necessary enhancements to released APIs. Therefore, the users of released APIs still have to consider the allowed compatible changes and access the APIs in such a way that the following errors and interruptions are avoided:

Problems during an upgrade.
Syntax errors after an upgrade.
Runtime errors after an upgrade.
Wrong behavior after an upgrade.

The following sections list rules for extensions to released APIs that must be considered when creating an extension.

Naming Rules
Rules for Extensions
Rules for Using Released DDIC Objects
Restrictions

Naming Rules

All extension field names must start with the correct namespace prefix.
All extension fields must have the element suffix that is defined in the released API by means of the annotation @AbapCatalog.enhancement.fieldSuffix.

Rules for Extensions

Only DDIC database tables and DDIC structures are available for C0 developer extensibility from a restricted ABAP language version.
The DDIC object must be released under the C0 contract for the corresponding language version (ABAP for Cloud Development or ABAP for Key Users).
All extension fields must be typed with a DDIC data element or with a built-in data type from the ABAP Dictionary using the syntax abap.type[(n)|(n,m)]. Typing with other structures or DDIC table types is not possible.
The extension must fit the quota definition and quota distribution defined in the extended object by means of the annotations @AbapCatalog.enhancement.quotaMaximumFields, @AbapCatalog.enhancement.quotaMaximumBytes, @AbapCatalog.enhancement.quotaShareCustomer, and @AbapCatalog.enhancement.quotaSharePartner.

Rules for Using Released DDIC Objects

When using a C0 released structure as include structure of another dictionary object, the addition WITH SUFFIX suffix must not be used.
When using a C0 released structure as include structure, this include structure must not be defined as a key using the addition KEY.
C0 released structures must not be used as include structure in any DDIC view.
When using a C0 released structure as include structure of another dictionary object, the value of the annotation @AbapCatalog.enhancement.category of the enclosing object must be greater than or equal to the enhancement category of the included structure. #EXTENSIBLE_ANY is greater than #EXTENSIBLE_CHARACTER_NUMERIC.
If a C0 released structure is included in any other DDIC object as include structure (syntax statement include), this inclusion must not be removed. The inclusion of a C0 released structure must remain stable. Otherwise, an ATC error occurs.

Restrictions

An extension must not define any element as a key field.
The following data types are not supported in extensions to released APIs: LCHR, LRAW, STRING, PREC, RAWSTRING, GEOM_EWKB, CHAR with length > 1333, RAW with length > 255.