Message type: E = Error
Message class:  CNV_PE_GEN - Messages for object generation 
Message number: 040
Message text: Data model DDIC generation is supported only for table parameters
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The SAP error message CNV_PE_GEN040 indicates that there is an issue with the data model generation process, specifically related to the use of table parameters in the context of the Data Dictionary (DDIC) generation. This error typically arises during the execution of a conversion or migration project, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: The error occurs because the system is attempting to generate a data model that includes parameters that are not recognized as table parameters. In SAP, table parameters are specific types of parameters that are used to handle multiple rows of data, and the generation process expects these parameters to be defined correctly in the data model.
Solution: To resolve this error, you can take the following steps: Check Parameter Definitions: Review the definitions of the parameters in your data model. Ensure that all parameters that are intended to be table parameters are correctly defined as such
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