Datasource append and data display

Hi gurus,

I am aiming to add ZTAG1 from T052 into 0ven_compc_attr dss zztag1 field.

At T052 key fields are MANDT ZTAGG ZTERM.

I have ZTERM in the datasources structure.

My code is as below.

when '0ven_compc_attr'.

  clear: l_s_data_ven_comp.

  loop at i_t_data into l_s_data_ven_comp.

    select single ztag1 from T052

      into l_s_data_ven_comp-zztag1

      where ZTERM = l_s_data_ven_comp-zterm AND

            ZTAGG = ''.

     modify i_t_data from l_s_data_ven_comp.

I donno why the rsa3 shows column ZZTAG1 however no data on the column although at T052 ztag1 is assigned for one particular zterm.

the code is not also passing to debug mode.

I would appreciate anyıne's help on that topic.

Regards.

Eddy.