Message type: E = Error
Message class:  RSO_RES_FRMW - BW REST Framework 
Message number: 009
Message text: Requested content type &2 does not match back-end content type &1
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The SAP error message RSO_RES_FRMW009 indicates a mismatch between the requested content type and the back-end content type in the context of SAP BW (Business Warehouse) or SAP BI (Business Intelligence) reporting. This typically occurs when there is an inconsistency between the data source and the way the data is being requested or displayed.
Cause: Content Type Mismatch: The requested content type (e.g., a specific format or structure of data) does not match the content type that the back-end system is configured to provide. This can happen if the data source has been changed or if there are discrepancies in the data model. Data Source Changes: If the underlying data source (like InfoProvider, query, or data model) has been modified, it may lead to this error if the changes are not reflected in the reporting layer. Query
Configuration Issues: The query might be configured to expect a certain type of data that is not
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