Message type: E = Error
Message class:  CNV_20100 - Messageclass for chart of account conversion 
Message number: 056
Message text: Check of the N:1 relationship was started on & & by &
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The SAP error message CNV_20100056 typically relates to issues encountered during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that there is a problem with the N:1 relationship check in the data being processed.
Cause: The error message CNV_20100056 suggests that the system has detected an inconsistency in the data relationships. Specifically, it indicates that the check for a many-to-one (N:1) relationship was initiated, but there may be issues such as: Data Inconsistency: There may be multiple entries in the source data that are trying to map to a single entry in the target data, which violates the expected N:1 relationship. Missing Data: The target data may not have the necessary entries to accommodate the relationships defined in the source data. Incorrect Mapping: The mapping rules defined for the migration may not correctly reflect the relationships in the source data.
Solution: To resolve the CNV_20100056 error,
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