How To Fix DDLS274 - CDS view of a view extend cannot be changed, in this case (&1->&2)

SAP Error Message - Details

• Message type: E = Error

• Message class: DDLS - For DDL source handling

• Message number: 274

• Message text: CDS view of a view extend cannot be changed, in this case (&1->&2)

What causes this issue?

The enhancement of an existing CDS view &V1& was assigned to a different
CDS view &V2&. This change is not allowed.
Due to an earlier programming error, this change may still have been
carried out.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

A new enhancement has to be created and this can then be assigned to CDS
view &V2&.
If this message occurs as a warning during an upgrade:
In this case, the change was still carried out. If &V1& is not activated
in its latest version during the upgrade, then &V1& should be
reactivated manually after the upgrade. This is required so that the
fields of the view extend of &V1& are removed.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message DDLS274 - CDS view of a view extend cannot be changed, in this case (&1->&2) ?

  The SAP error message DDLS274 indicates that you are trying to change a CDS (Core Data Services) view that is extending another CDS view, but the system does not allow this operation. This typically occurs when you attempt to modify the definition of a CDS view that is already being extended by another view.
  Cause:
  
  CDS View Extension: The error arises because the CDS view you are trying to change is being extended by another CDS view. In SAP, when a CDS view is extended, it creates a dependency that prevents changes to the original view's structure (like adding or removing fields) without first addressing the extensions.
  Dependency Management: SAP enforces strict dependency management to ensure that changes do not break existing functionality or data integrity. If a view is extended, any changes to the base view could potentially affect the extending views.
  
  Solution:
  
  Check Dependencies: Identify the CDS views that are extending the view you want to change. You can do this by checking the "Where-Used List" for the CDS view in the ABAP Development Tools (ADT) or using transaction SE11.
  Modify Extending Views: If you need to change the base view, you will first need to modify or delete the extending views. This may involve:
  
  Adjusting the extending views to accommodate the changes you want to make.
  Temporarily deactivating the extending views if they are not needed during the change.
  
  
  Change the Base View: Once the dependencies are resolved, you can proceed to make the necessary changes to the base CDS view.
  Re-activate Extending Views: After making the changes to the base view, you can reactivate the extending views, ensuring they still function correctly with the updated base view.
  
  Related Information:
  
  CDS Views: Core Data Services are a way to define semantically rich data models in SAP. They allow for the creation of views on database tables and other views, enabling complex data retrieval scenarios.
  ABAP Development Tools (ADT): This is the recommended environment for developing and managing CDS views, as it provides tools for checking dependencies and managing view definitions.
  SAP Notes and Documentation: Always refer to the latest SAP Notes and documentation for updates on CDS view behavior and best practices.
  
  By following these steps, you should be able to resolve the DDLS274 error and successfully modify your CDS views as needed.