Short Dump....itab

Question

Hai All,
I have done an ALV Report Program, which while executing goes to the short dump and the error msg says:
" You attempted to change, delete or create a line in the internal table "???", but no valid cursor exists for the table.
Possible reasons:
1.The relevant Abap/4 statement does not include the addition "..INDEX.." although the statement is not inside a "LOOP..Endloop" loop processing this table.
2.The relevant Abap/4 statement was called from within a "Loop..Endloop" loop after a Delete"???". "
Could anyone sort this out please.
Thanks in Advance.
rama

Answer 1

Yes, I am trying to modify my internal table: Here is my code:
How can i use the index here:
select * into corresponding fields of table itab from bsis
                                      where bukrs in x_bukrs
                                        and hkont in x_hkont
                                        and budat in x_budat
                                        and bldat in x_bldat
                                        and zuonr in x_zuonr.
*data
move-corresponding itab to jtab.
loop at itab.   " into wa_itab.
if itab-shkzg = 'H'.
*move-corresponding itab to jtab.
x_dmbtr = itab-dmbtr * ( -1 ).
move x_dmbtr to jtab-dmbtr.
x_vbeln = itab-zuonr+0(9).
move x_vbeln to jtab-vbeln.
*append wa_jtab to jtab.
modify jtab transporting dmbtr vbeln.
*collect jtab.
else.
*move-corresponding itab to jtab.
x_dmbtr = itab-dmbtr.
x_vbeln = itab-zuonr+0(9).
move x_vbeln to jtab-vbeln.
*append wa_jtab to jtab.
modify jtab transporting dmbtr vbeln.
*collect jtab.
endif.
collect jtab.
endloop.