Create a structure from a dynamically assigned <itab>

Question

In a method I have a reference to a table that was declared like this:

DATA: tabname TYPE tabname,
      dref    TYPE REF TO data,
FIELD-SYMBOLS: <itab> TYPE ANY TABLE.

CREATE DATA dref TYPE TABLE OF (tabname).
ASSIGN dref->* TO <itab>.

SELECT * FROM (tabname)
    UP TO 5 ROWS
  INTO TABLE <itab>.

How do I create a structure based on ?

Answer 1

Just use good ol' RTTS for that. You can create reference and read directly into it

FIELD-SYMBOLS: <itab> TYPE STANDARD TABLE.
DATA: ref_wa        TYPE REF TO data,
      ref_rowtype   TYPE REF TO cl_abap_structdescr,
      ref_tabletype TYPE REF TO cl_abap_tabledescr.

ref_rowtype ?= cl_abap_typedescr=>describe_by_name( tabname ).

CREATE DATA ref_wa TYPE HANDLE ref_rowtype.
READ TABLE <itab> REFERENCE INTO ref_wa INDEX 1.

or create field-symbol based on this reference and use it in READ TABLE

ASSIGN ref_wa->*  TO FIELD-SYMBOL(<fsym_wa>).
READ TABLE <itab> ASSIGNING <fsym_wa> INDEX 1.

Pay attention I declared <itab> as STANDARD table to get rid of index error operation you got.

UPDATE: for creating structure from <itab> object use this syntax:

ref_tabletype ?= cl_abap_typedescr=>describe_by_data( <itab> ).
ref_rowtype  ?= ref_tabletype->get_table_line_type( ).

The last two lines will be identical.

Answer 2

You can use inline declaration to define WA like this. READ TABLE <itab> INTO (<wa>) or declare WA/Field symbol first using FIELD SYMBOL <wa> TYPE ANY then read table with READ TABLE <tab> ASSIGNING <wa>

Answer 3

1.You define a ANY field symbol ans use ASSIGNING

 FIELD-SYMBOLS:
      <line> type any.

 LOOP at <itab> ASSIGNING <line>.

 ENDLOOP.

2.You define a ANY field symbol ans use INTO

 FIELD-SYMBOLS:
      <line> type any.

 CREATE DATA dref like line of <itab>.
 ASSIGN dref->* to <line>.

 LOOP at <itab> INTO <line>.

 ENDLOOP.