Message type: E = Error
Message class:  FKKBIX - Conv.Inv.: Billing (Invoice Preprocessing) 
Message number: 669
Message text: Database view &1 is still being used and cannot be deleted
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The SAP error message FKKBIX669 indicates that a database view is still in use and cannot be deleted. This typically occurs when there are dependencies or references to the database view in question, which prevents its deletion.
Cause: Active Dependencies: The database view is being referenced by other database objects, such as tables, views, or programs. Open Transactions: There may be open transactions or sessions that are currently using the database view. Data Dictionary Objects: The view might be linked to data dictionary objects that are still active or in use.
Solution: To resolve this error, you can follow these steps: Check Dependencies: Use transaction code SE11 (Data Dictionary) to check the dependencies of the database view. You can do this by entering the view name and selecting the "Where-Used List" option to see where the view is being referenced. Identify and address any dependencies that are preventing the deletion. Close Open Sessions: Ensure that there are no active sessions or
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