Message type: E = Error
Message class:  RSO_RES_QMSGS - Messages directly related to Query Designer. 
Message number: 251
Message text: Query cannot be used in formula mode due to existing exceptions. &1
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The SAP error message RSO_RES_QMSGS251 indicates that a query cannot be used in formula mode because there are existing exceptions defined in the query. This typically occurs in SAP BW (Business Warehouse) when you are trying to use a query that has exceptions defined in its structure, which are not compatible with the formula mode.
Cause: The primary cause of this error is that the query you are trying to use has exceptions (like filters, conditions, or specific formatting rules) that prevent it from being processed in formula mode. Formula mode is used for calculations and aggregations, and the presence of exceptions can lead to conflicts or inconsistencies in the results.
Solution: To resolve this error, you can take the following steps: Check Query Design: Open the query in the Query Designer. Review the exceptions defined in the query. Look for any filters, conditions, or formatting that might be causing the issue. Modify or Remove Exceptions: If possible, modify
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