How To Fix SADL_GW_DT_CDS002 - Calculated field &1 is not allowed.

SAP Error Message - Details

• Message type: E = Error

• Message class: SADL_GW_DT_CDS - Messages CDS Checks

• Message number: 002

• Message text: Calculated field &1 is not allowed.

What causes this issue?

In the CDS view (consumption view), a calculated field is defined:
e.g.: so.NetAmount + so.TaxAmount as GrossAmount
A field can only be calculated using a calculation exit.

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?

Create an ABAP class (CL_xxx_EXIT) which implements the interface
IF_SADL_EXIT_CALC_ELEMENT_READ where the field is calculated.
Add the annotations to the field in the CDS view (consumption view):
@ObjectModel: { virtualElement : true<(>,<)>
virtualElementCalculatedBy: 'ABAP:CL_xxx_EXIT'
}
cast( 0 as MYAMOUNT ) as GrossAmount<(>,<)>

Procedure for System Administrators

Contact the corresponding developer of the CDS view to correct the
error.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message SADL_GW_DT_CDS002 - Calculated field &1 is not allowed. ?

  The SAP error message SADL_GW_DT_CDS002 indicates that a calculated field is not allowed in the context of the operation you are trying to perform. This error typically arises when working with Core Data Services (CDS) views in SAP, particularly when using the SAP Gateway or when trying to expose CDS views as OData services.
  Cause:
  
  Calculated Fields: The error occurs because the CDS view contains a calculated field that is not supported in the context of the operation. This can happen if the calculated field is not defined correctly or if it is not allowed to be used in the specific scenario (e.g., in an OData service).
  OData Service Limitations: Certain calculated fields may not be compatible with the OData service due to the way they are defined or the data types involved.
  Data Model Constraints: The underlying data model may impose restrictions on the use of calculated fields, especially if they are not part of the primary data structure.
  
  Solution:
  
  Review the CDS View: Check the definition of the CDS view to ensure that the calculated field is defined correctly. Make sure that it is not overly complex or using unsupported functions.
  Modify the Calculated Field: If possible, consider removing the calculated field or replacing it with a simple field that is allowed in the context of the OData service.
  Use Annotations: If the calculated field is necessary, consider using annotations to define how it should be handled in the OData service. This may involve adjusting the way the field is exposed.
  Check OData Service Configuration: Ensure that the OData service is configured correctly to handle the fields defined in the CDS view. You may need to regenerate the service or adjust the service definition.
  Consult Documentation: Refer to the SAP documentation for Core Data Services and OData services to understand the limitations and best practices for using calculated fields.
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide guidance on best practices for using calculated fields in CDS views.
  SAP Community: Engage with the SAP Community forums to see if other users have encountered similar issues and what solutions they have found.
  Debugging: If you have access to the development environment, consider debugging the CDS view and the OData service to identify the exact point of failure and gather more context about the error.
  
  By following these steps, you should be able to resolve the error and successfully work with your CDS views and OData services.