Message type: E = Error
Message class:  SDDIC_CSN - CSN Exporter Runtime Messages 
Message number: 018
Message text: Query not exported. Element &2 of entity &1 has unsupported expression.
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The SAP error message SDDIC_CSN018 indicates that there is an issue with a query not being exported due to an unsupported expression in one of the elements of the entity. This typically occurs in the context of SAP Data Services or SAP BW (Business Warehouse) when trying to export or execute a query that contains elements or expressions that are not supported by the system.
Cause: Unsupported Expressions: The error usually arises when the query includes calculated fields, complex expressions, or unsupported functions that cannot be processed by the export mechanism. Data Type Mismatch: There may be a mismatch in data types or formats that the query is trying to handle. Entity Configuration: The entity configuration may not be set up correctly, leading to unsupported elements being included in the query. Version Compatibility: There may be compatibility issues between different versions of SAP components or between SAP and third-party tools.
Solution: Review the Query: Check the query
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