Message type: E = Error
Message class:  CNV_PE_CHECK - Check Framework messages for posting engine 
Message number: 304
Message text: Transformation rule type is empty
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The SAP error message CNV_PE_CHECK304 indicates that a transformation rule type is empty in the context of a data migration or conversion process, typically associated with the SAP S/4HANA Migration Cockpit or other data migration tools. This error usually arises during the mapping or transformation phase of data migration when the system expects a specific rule type to be defined but finds it missing.
Cause: Missing Configuration: The transformation rule type has not been defined in the migration project. Incorrect Mapping: The mapping of fields from the source to the target system may not have been set up correctly. Data Model Changes: Changes in the data model or structure may have led to the absence of required transformation rules. Incomplete Migration Template: The migration template may not have been fully populated with the necessary transformation rules.
Solution: Define Transformation Rules: Go to the migration project in the SAP system. Check the transformation rules for the relevant data objects. Ensure that
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