Message type: E = Error
Message class:  RSO_RES_QMSGS - Messages directly related to Query Designer. 
Message number: 026
Message text: Non-supported query structure detected in element &1
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The SAP error message RSO_RES_QMSGS026 indicates that a non-supported query structure has been detected in a specific element of a query. This typically occurs in the context of SAP BW (Business Warehouse) or SAP BI (Business Intelligence) when working with queries in BEx (Business Explorer) or when trying to execute or analyze queries that have been improperly defined or have incompatible structures.
Cause: Incompatible Query Structure: The query may contain elements or structures that are not supported by the current version of the query or the underlying data model. Changes in Data Model: If there have been changes to the InfoProvider or the underlying data model (like changes in InfoObjects, characteristics, or key figures), it may lead to this error. Query Definition Issues: The query might have been defined incorrectly, such as using unsupported combinations of characteristics or key figures. Transport Issues: If the query was transported from one system to another, there might be
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