Regarding appending data in table type

Hello Experts,

Actually, I have one structure and in that I am using one table type .

e.g. in the main structure, fields are as follows,

po_number po_line_item_no gr_details

here gr_details is table type having following fields.

gr_number gr_qty gr_date

As we all know that one po can have multiple GR,

I want to append entries in the above structure in such a way that for one po entry , in the same record , multiple Gr entries should come.

I am doing one program , in it is mendatory.

can anyone please revert back on the same with High Priority ( Coding in Program to append values as per explained above ).

Best Regards,

Rashmi.