Message type: E = Error
Message class:  SADL_RAP_OPXY_EDMX - RESTful ABAP Odata Proxy Support 
Message number: 057
Message text: Entity Set &1 : Navigation property has no name
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The SAP error message SADL_RAP_OPXY_EDMX057 typically indicates an issue with the navigation properties in the Entity Data Model (EDM) when working with the RAP (Rapid Application Programming) model in SAP. This error suggests that there is a navigation property defined in your entity set that does not have a name, which is required for proper functioning.
Cause: Missing Navigation Property Name: The navigation property in the entity definition is not properly defined or is missing a name. Model Definition Issues: There may be inconsistencies or errors in the way the entity model is defined, particularly in the annotations or the relationships between entities. Code Generation Issues: If the code was generated automatically, there might have been an issue during the generation process that led to incomplete or incorrect definitions.
Solution: Check Entity Definition: Review the entity definition in your CDS (Core Data Services) view or the relevant data model. Ensure that all navigation properties are correctly
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