How To Fix /IWBEP/CM_V4_MED308 - Advertising property '&1' in entity type '&2' must not be key

SAP Error Message - Details

• Message type: E = Error

• Message class: /IWBEP/CM_V4_MED -

• Message number: 308

• Message text: Advertising property '&1' in entity type '&2' must not be key

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message /IWBEP/CM_V4_MED308 - Advertising property '&1' in entity type '&2' must not be key ?

  The SAP error message /IWBEP/CM_V4_MED308 indicates that there is an issue with the definition of an entity type in your OData service. Specifically, the error states that an advertising property (a property that is intended to be exposed in the OData service) is being defined as a key property, which is not allowed.
  Cause:
  In OData, key properties are used to uniquely identify an entity instance. Advertising properties, on the other hand, are typically used for additional information that does not uniquely identify an entity. The error occurs when you attempt to define a property as both a key and an advertising property, which violates the OData protocol.
  Solution:
  To resolve this error, you need to check the entity type definition in your OData service and ensure that the property in question is not marked as a key if it is intended to be an advertising property. Here are the steps to fix the issue:
  
  
  Open the Data Model: Access the data model where the entity type is defined.
  
  
  Identify the Property: Locate the property that is causing the error (indicated by &1 in the error message) in the entity type (indicated by &2).
  
  
  Check Key Definition: Review the key definition for the entity type. Ensure that the property is not included in the key properties list if it is meant to be an advertising property.
  
  
  Modify the Definition: If the property is incorrectly defined as a key, remove it from the key properties list. If it is supposed to be a key, then it should not be marked as an advertising property.
  
  
  Activate the Changes: After making the necessary changes, activate the data model and regenerate the OData service.
  
  
  Test the Service: Finally, test the OData service to ensure that the error is resolved and that the service behaves as expected.
  
  
  Related Information:
  
  OData Protocol: Understanding the OData protocol and its conventions regarding entity types, keys, and properties can help prevent similar issues in the future.
  SAP Gateway: Familiarize yourself with SAP Gateway and how it handles OData services, as this will provide context for how entity types and properties are defined and managed.
  SAP Notes and Documentation: Check SAP Notes and official documentation for any updates or additional guidance related to OData service development and error handling.
  
  By following these steps, you should be able to resolve the error and ensure that your OData service is correctly configured.