Create a data element

Go back to the class, **ZCL_INVOICE_RETRIEVAL**, which you created in the previous tutorial, (Create an ABAP class).)
You will now transform the values of payment_status from P to a flag that is set to X (true) when the invoice has been paid.

Enter the following code after the ORDER BY clause of the SELECT statement:

LOOP AT lt_result ASSIGNING FIELD-SYMBOL(<entry>).
    CASE <entry>-payment_status.
        WHEN 'P'.
            <entry>-payment_status = abap_true.
        WHEN OTHERS.
            <entry>-payment_status = abap_false.
    ENDCASE.
ENDLOOP.

Finally, choose Save (Ctrl+S), then Activate (Ctrl+F3) your class.

Your code should look like this:

CLASS zcl_invoice_retrieval DEFINITION
  PUBLIC
  FINAL
  CREATE PUBLIC .

  PUBLIC SECTION.
    TYPES: ty_table_of_zso_invoice_item TYPE STANDARD TABLE OF zso_invoice_item WITH DEFAULT KEY.

    METHODS get_items_from_db
              RETURNING
                VALUE(lt_result) type ty_table_of_zso_invoice_item.
  PROTECTED SECTION.
  PRIVATE SECTION.
ENDCLASS.

CLASS zcl_invoice_retrieval IMPLEMENTATION.

  METHOD get_items_from_db.

  SELECT
    snwd_bpa~company_name,
    snwd_so_inv_item~gross_amount,
    snwd_so_inv_item~currency_code,
    snwd_so_inv_head~payment_status

  FROM
   snwd_so_inv_item
   JOIN snwd_so_inv_head ON snwd_so_inv_item~parent_key = snwd_so_inv_head~node_key
   JOIN snwd_bpa ON snwd_so_inv_head~buyer_guid = snwd_bpa~node_key

   INTO TABLE @lt_result

  WHERE
   snwd_so_inv_item~currency_code = 'USD'

  ORDER BY
   snwd_bpa~company_name.

   LOOP AT lt_result ASSIGNING FIELD-SYMBOL(<entry>).
        CASE <entry>-payment_status.
            WHEN 'P'.
                <entry>-payment_status = abap_true.
            WHEN OTHERS.
                <entry>-payment_status = abap_false.
        ENDCASE.
    ENDLOOP.
  ENDMETHOD.
ENDCLASS.