How to pass single-column table to AMDP method?

Question

I need to pass a table with a single column to an AMDP method which throws the error, the other parameters go fine:

TYPES: BEGIN OF s_so_i,
         parent_key   TYPE snwd_so_i-parent_key,
         product_guid TYPE snwd_pd-node_key,
         node_key     TYPE snwd_so_i-node_key,
       END OF s_so_i.
TYPES: BEGIN OF s_product,
         product_guid TYPE snwd_pd-node_key,
         category     TYPE snwd_pd-category,
       END OF s_product.
TYPES: tt_product TYPE STANDARD TABLE OF s_product,
       tt_so      TYPE STANDARD TABLE OF snwd_node_key,  "<-- error
       tt_so_i    TYPE STANDARD TABLE OF s_so_i.

How should I define it?

Answer 1

Adding this solved the problem:

TYPES: BEGIN OF s_so,
         so_guid TYPE snwd_so-node_key,
       END OF s_so.

TYPES: tt_product TYPE STANDARD TABLE OF s_product,
       tt_so_i    TYPE STANDARD TABLE OF s_so_i,
       tt_so      TYPE STANDARD TABLE OF s_so.  <--

So it seems the table type must point to a structure type.