Message type: E = Error
Message class:  CNV_10020 - Message class for package 10020 
Message number: 408
Message text: &1 elementary relationships were marked for loading
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The SAP error message CNV_10020408 typically occurs during data migration processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. This error indicates that a certain number of elementary relationships (data relationships that are fundamental to the data model) have been marked for loading but have not been processed correctly.
Cause: Data Integrity Issues: The error may arise due to inconsistencies or integrity issues in the source data. For example, if there are missing references or relationships that are required for the data to be loaded correctly.
Configuration Issues: Incorrect configuration settings in the migration tool or the data model can lead to this error. Mapping Errors: If the mapping of source data to target data is not correctly defined, it can result in relationships not being established properly. Missing Dependencies: If the data being loaded has dependencies on other data that has not yet been loaded, this can cause the
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