Message type: E = Error
Message class:  DDLS - For DDL source handling 
Message number: 516
Message text: At least one base view is an external view and not supported on DB &
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The SAP error message DDLS516 indicates that there is an issue with a database view definition in the context of a database that does not support certain types of views, specifically external views. This error typically arises when you are trying to create or modify a database view that includes an external view, which is not supported by the underlying database system.
Cause: External Views: The error occurs because at least one of the base views used in the definition of the view you are trying to create or modify is an external view. External views are views that reference data from another database or system, and not all databases support them. Database Compatibility: The database you are working with may not support the specific features or types of views that are being referenced in your view definition. Incorrect View Definition: The view definition may be incorrectly set up, leading to the inclusion of
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