Message type: E = Error
Message class:  RSO_RES_QMSGS - Messages directly related to Query Designer. 
Message number: 151
Message text: No value assigned to variable &1.
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
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The SAP error message RSO_RES_QMSGS151, which states "No value assigned to variable &1," typically occurs in the context of SAP BW (Business Warehouse) or SAP BI (Business Intelligence) when a query is executed, and a required variable does not have a value assigned to it. This can happen in various scenarios, such as when running a report or executing a query that relies on input variables.
Cause: Missing Variable Value: The variable referenced by &1 has not been assigned a value. This can happen if the user did not provide a value when prompted or if the variable is not set up correctly in the query. Default Values: If the variable is supposed to have a default value and it is not set, the query will fail to execute. Variable Type: The variable may be of a type that does not allow for a default value or is not properly configured. User Authorization: The user
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