Message type: E = Error
Message class:  CNV_10020 - Message class for package 10020 
Message number: 787
Message text: &1 cardinalities were loaded
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The SAP error message CNV_10020787 typically relates to issues encountered during data migration or conversion processes, particularly when using SAP's data migration tools. The message indicates that there is a problem with the cardinalities of the data being loaded, which means that the relationships between different data entities (like one-to-one, one-to-many, or many-to-many) are not being respected or are not as expected.
Cause: Data Model Mismatch: The source data may not match the expected data model in the target system. For example, if the target system expects a one-to-many relationship but the source data has a many-to-many relationship, this can trigger the error. Data Quality Issues: There may be duplicates or missing data in the source that violate the expected cardinalities.
Configuration Issues: Incorrect configuration settings in the migration tool or the target system can lead to cardinality mismatches. Transformation Logic Errors: If there are errors in the transformation logic that processes the data before
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