Decision Table in Web Based Development Workbench + UDF Function in CDS

Hi experts,

1. I want to use a decision table, but I'm modelling with the Web Based Development Workbench. I did not find any way to create one. Is there any?

2. Is there a possibility to create UDF table functions in the Web Based Development Workbench. Is it possible by the .hdbtablefunction or even by CDS?

3. I want to pass a two values into a procedure within a graphical calc view and return the output of the procedure as column. Is there any way?

Thanks and best regards

Johannes