Dynamic ITAB, SQL, and retrieving itab definition

REPORT  z_dyn_test                            .

TYPE-POOLS : abap.
FIELD-SYMBOLS: <dyn_table> TYPE STANDARD TABLE,
               <dyn_wa>,
               <dyn_field>.
DATA: dy_table TYPE REF TO data,
      dy_line  TYPE REF TO data,
      xfc TYPE lvc_s_fcat,
      ifc TYPE lvc_t_fcat.
SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME.
PARAMETERS: p_table(30) TYPE c DEFAULT 'T001'.
SELECTION-SCREEN END OF BLOCK b1.

START-OF-SELECTION.
  PERFORM get_structure.
  PERFORM create_dynamic_itab.
  PERFORM get_data.
  PERFORM write_out.
*---------------------------------------------------------------------*
*       FORM get_structure                                            *
*---------------------------------------------------------------------*
FORM get_structure.
  DATA : idetails TYPE abap_compdescr_tab,
         xdetails TYPE abap_compdescr.
  DATA : ref_table_des TYPE REF TO cl_abap_structdescr.

  ref_table_des ?=
        cl_abap_typedescr=>describe_by_name( p_table ).
  idetails[] = ref_table_des->components[].
  LOOP AT idetails INTO xdetails.
    CLEAR xfc.
    xfc-fieldname = xdetails-name .
*    xfc-datatype = xdetails-type_kind.
    xfc-inttype = xdetails-type_kind.
    xfc-intlen = xdetails-length + xdetails-decimals.
    xfc-decimals = xdetails-decimals.
    APPEND xfc TO ifc.
  ENDLOOP.
ENDFORM.                    "get_structure
*---------------------------------------------------------------------*
*       FORM create_dynamic_itab                                      *
*---------------------------------------------------------------------*
FORM create_dynamic_itab.

  CALL METHOD cl_alv_table_create=>create_dynamic_table
    EXPORTING
      it_fieldcatalog = ifc
    IMPORTING
      ep_table        = dy_table.
  ASSIGN dy_table->* TO <dyn_table>.

  CREATE DATA dy_line LIKE LINE OF <dyn_table>.
  ASSIGN dy_line->* TO <dyn_wa>.
ENDFORM.                    "create_dynamic_itab

*---------------------------------------------------------------------*
*       FORM get_data                                                 *
*---------------------------------------------------------------------*
FORM get_data.
  DATA: BEGIN OF itab OCCURS 0 .
          INCLUDE STRUCTURE spfli.
  DATA: END OF itab.

  SELECT * INTO CORRESPONDING FIELDS OF TABLE <dyn_table>
             FROM (p_table).
ENDFORM.                    "get_data
*---------------------------------------------------------------------*
*       FORM write_out                                                *
*---------------------------------------------------------------------*
FORM  write_out.
  LOOP AT <dyn_table> INTO <dyn_wa>.
    DO.
      ASSIGN COMPONENT  sy-index
         OF STRUCTURE <dyn_wa> TO <dyn_field>.
      IF sy-subrc <> 0.
        EXIT.
      ENDIF.
      IF sy-index = 1.
        WRITE:/ <dyn_field>.
      ELSE.
        WRITE: <dyn_field>.
      ENDIF.
    ENDDO.
  ENDLOOP.
ENDFORM.                    "write_out

 

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