How to get a varchar type out of a hdbdd-model?

Hello,

I'd like to define the tree model input table type for the PAL function PREDICTWITHDT within CDS via an hdbdd-file. The tree model input data type needs varchar(5000), but string(5000) in hdbdd generates nvarchar(5000). When trying to use this tree model table with type nvarchar(5000) as input table in the AFM for the "Predict with Decision Tree" algorithm, one gets an error telling that the table column setting does not match the function specification.

Is there any possibility to get varchar from hdbdd?

Thanks,

Ingo