How To Fix SD_CDS_PROJECTION008 - Multiple usage of field &1 is not allowed in projection views

SAP Error Message - Details

• Message type: E = Error

• Message class: SD_CDS_PROJECTION - Message for Projection Entities

• Message number: 008

• Message text: Multiple usage of field &1 is not allowed in projection views

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message SD_CDS_PROJECTION008 - Multiple usage of field &1 is not allowed in projection views ?

  The SAP error message SD_CDS_PROJECTION008 indicates that there is a problem with the definition of a projection view in Core Data Services (CDS) where a field is being used multiple times. This is not allowed in projection views, as each field must be unique within the projection.
  Cause:
  The error occurs when:
  
  A field is included more than once in the projection view definition.
  The same field is being selected from different sources or aliases, leading to ambiguity.
  
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Review the Projection View Definition:
  
  Check the definition of your projection view in the CDS view. Look for any fields that are being selected multiple times.
  
  
  
  Remove Duplicate Fields:
  
  Ensure that each field is included only once in the projection. If you need to include the same field from different sources, consider using aliases or restructuring your view.
  
  
  
  Use Aliases:
  
  If you need to reference the same field from different tables or sources, use aliases to differentiate them. However, ensure that the same field is not selected multiple times without an alias.
  
  
  
  Check for Inherited Fields:
  
  If your projection view is based on another view or entity, check if the inherited fields are causing duplicates. You may need to redefine the base view or adjust the projection.
  
  
  
  Test the Changes:
  
  After making the necessary adjustments, activate the CDS view and test it to ensure that the error is resolved.
  
  
  
  Related Information:
  
  CDS Views: Core Data Services (CDS) are a way to define semantic data models in SAP. They allow for the creation of complex data models that can be consumed by various applications.
  Projection Views: These are a type of CDS view that allows you to select specific fields from a data source. They are used to create a simplified view of the data.
  SAP Documentation: For more detailed information, refer to the official SAP documentation on CDS views and projection views, which provides guidelines and best practices for defining them.
  
  By following these steps, you should be able to resolve the SD_CDS_PROJECTION008 error and successfully define your projection view.