Macro in ABAP Code

Question

Dear All,
I am trying to debug a Macro in SAP standard Extractor. I am unable to understand the line in bold. following is the Macro code:
DEFINE sel.
    when &1.
      sort s_t_select by fieldnm.        
      do.
        fetch next cursor g_cursor into id.
        if sy-subrc eq 0.
<b>          import &2 from database &3(bw) id id.</b>   
      loop at &2.
            cond_select = true.
            loop at s_t_select.
"delete" entry if select-option does not fit
              assign component s_t_select-fieldnm of
                structure &2 to <fs_field>.
              if sy-subrc ne 0.
                log_write 'E'          "message type
                          'MCEX'       "message class
                          '022'        "message number
                          i_isource    "message variable 1
                          s_estruc.    "message variable 2
                raise error_passed_to_mess_handler.
              endif.
         move-corresponding s_t_select to cond_select_tab.
         append cond_select_tab.
         at end of fieldnm.
                if not <fs_field> in cond_select_tab.
                  cond_select = false.
                  refresh cond_select_tab.        
                  exit.
                endif.
               refresh cond_select_tab.           
              endat.                              
            endloop.
            if cond_select eq true.
              append &2 to e_t_data.
              add 1 to counter.
            endif.
          endloop.
          if s_maximum_size le counter.
            exit.
          endif.
        else.
          close cursor g_cursor.
          s_flg_no_more_data = true.
          exit.
        endif.
      enddo.
    END-OF-DEFINITION.
The call is as follow:
sel 'MC13VD0ITM' mc13vd0itm_tab  mc13vd0itmsetup.

Answer 1

Hi pooja,
1. import &2 from database &3(bw) id id.
  IMPORT
  (See F1 Help )
2. The macro line
   is importing
   from database cluster :
   internal table &2
   from cluster table &3
3. where &2 &3 are the parameters
   passed to the macro while calling.
regards,
amit m.