Here is a sample program in which used two internal tables:

REPORT YPRINTPRG_SMARTFORM1 .
DATA : ITKNA1 LIKE KNA1,
             ITVBAK LIKE VBAK OCCURS 0 WITH HEADER LINE.
PARAMETERS : PKUNNR LIKE KNA1-KUNNR.

SELECT * FROM KNA1 INTO ITKNA1
   WHERE KUNNR = PKUNNR.
ENDSELECT.

SELECT * FROM VBAK
    INTO TABLE ITVBAK
   WHERE KUNNR = PKUNNR.

CALL FUNCTION '/1BCDWB/SF00000011' “THIS FUNCTION MODULE CALLS THE 
                                      SMART FORM WE WILL GET THIS AT MENU ENVIRONEMENT ”
  EXPORTING
  ITKNA1                     = ITKNA1
  TABLES
      ITVBAK                = ITVBAK.

IN SMART FORM 
FORM INERFACE---------IMPORT (TAB) 
  Parameter name      Type assignment    Reference type      Default value 
  ITKNA1                     LIKE                      KNA1

FORM INERFACE---------TABLES (TAB)
  ITVBAK                     LIKE                       VBAK

PAGES & WINDOWS----- MAIN WINDOW-----LOOP 1----DATA(TAB)
  ITVBAK         INTO               ITVBAK

PAGES & WINDOWS-------MAIN WINDOW------LOOP 1-----TEXT 3(EDITOR) 
  &ITVBAK-VBELN&   &ITVBAK-ERDAT&  &ITVBAK-ERNAM&  &ITVBAK-NETWR&

PAGES & WINDOWS-------HEADER WINDOW-----TEXT 2(EDITOR)
  Customer No. &itkna1-kunnr&        CustomerName :&itkna1-name1&

Tips by : Vijay

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