How To Fix /IWBEP/CM_CP098 - Invalid return cardinality for V2 operation '&1'

SAP Error Message - Details

• Message type: E = Error

• Message class: /IWBEP/CM_CP -

• Message number: 098

• Message text: Invalid return cardinality for V2 operation '&1'

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message /IWBEP/CM_CP098 - Invalid return cardinality for V2 operation '&1' ?

  The SAP error message /IWBEP/CM_CP098 Invalid return cardinality for V2 operation '&1' typically occurs in the context of SAP Gateway and OData services. This error indicates that there is a mismatch between the expected return cardinality of an OData operation and the actual return cardinality defined in the service.
  Cause:
  
  Cardinality Mismatch: The error usually arises when the OData service is defined to return a certain number of records (e.g., one or many), but the implementation of the service does not conform to this definition.
  Service Definition Issues: The service might be incorrectly defined in the Service Builder (SEGW) transaction, where the return type of an operation (e.g., GET, POST) does not match the expected cardinality.
  Model Issues: The data model might not be correctly set up to handle the expected return type, leading to inconsistencies.
  
  Solution:
  
  
  Check Service Definition:
  
  Go to the Service Builder (transaction SEGW).
  Open the relevant service and check the operation that is causing the error.
  Ensure that the return type and cardinality (1..1, 0..1, 1..n, etc.) are correctly defined according to the business logic.
  
  
  
  Adjust Implementation:
  
  If the implementation of the operation (in the DPC class) is returning a different cardinality than defined, adjust the code to ensure it matches the expected return type.
  For example, if the operation is defined to return a single entity but the implementation returns a table, you need to modify the implementation to return a single entity.
  
  
  
  Regenerate the Service:
  
  After making changes to the service definition or implementation, regenerate the service to ensure that all changes are applied.
  Use the "Generate Runtime Objects" option in the Service Builder.
  
  
  
  Test the Service:
  
  After making the necessary adjustments, test the OData service using the SAP Gateway Client (transaction /IWFND/GW_CLIENT) or any other OData client to ensure that the error is resolved.
  
  
  
  Related Information:
  
  OData Service Documentation: Familiarize yourself with OData service definitions and cardinality rules. The SAP Help Portal provides extensive documentation on OData services.
  Debugging: If the issue persists, consider debugging the service implementation to trace the flow of data and identify where the mismatch occurs.
  SAP Notes: Check for any relevant SAP Notes that might address known issues or provide additional guidance on this error.
  
  By following these steps, you should be able to resolve the /IWBEP/CM_CP098 Invalid return cardinality for V2 operation '&1' error in your SAP environment.