Message type: E = Error
Message class:  SADL_GW_DT_CDS - Messages CDS Checks 
Message number: 009
Message text: &1: Annotation &2 is missing. Add the annotation to the CDS view.
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The SAP error message SADL_GW_DT_CDS009 indicates that there is a missing annotation in a Core Data Services (CDS) view that is required for the proper functioning of the SAP Gateway or the OData service. This error typically arises when the CDS view is expected to have certain annotations that define how the data should be exposed or consumed, but those annotations are not present.
Cause: The error is caused by the absence of a required annotation in the CDS view. Annotations in CDS views are used to provide metadata about the data model, such as how it should be serialized, which fields should be exposed, and how they should be formatted. The specific annotation that is missing is indicated in the error message (denoted as &2).
Solution: To resolve this error, you need to add the missing annotation to the CDS view. Here are the steps to do that: Identify the Missing Annotation: Check the
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What causes this issue?  In the consumption CDS view, a virtual element is used in an association definition. This is not allowed.System Response  The...
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