ODATA & SQL how to define GET_ENTITYSET

Hi Experts,

I need to define an OData GET_ENITITYSET Method in the SEGW.

I created a Datamodel from the GET_GPU_ALL function and the stub could generate the classes without error.

How can I get the Information from the Table.

I know I need to use SQL.

I tried SELECT * FROM OSMON into

CORRESPONDING FIELDS OF TABLE et_entityset.

But the system is not able to find all of the data. I´m getting some JSON Response but not all of the data I`ll consume.

I know the data from the function group GET_CPU_ALL are stored in Table TF_CPU_ALL but when I am trying

SELECT * FROM TF_CPU_ALL I am getting an errror says no such TABLE defined.

Moreover I know that there are no really innter tables in SAP there like JOINS....

But I connot figure out which SQL Phrase I have to use to get the data from the TF_CPU_ALL (Table).

I would really appreciate if someone could suggest me a solution or give me an hint to sove the problem.

Thank you.

Joe