How to avoid nested loop?

[walkerist79]

Here is my current situation: 
DATA: T_FCAT1 TYPE slis_fieldcat_alv,
      t_fcat TYPE kkblo_t_fieldcat.
LOOP AT T_FCAT1 INTO LX_FCAT1.
    LOOP AT LT_FCATALOG INTO LX_FCATALOG.
    IF LX_FCAT1-FIELDNAME = LX_FCATALOG-FIELDNAME.
         LX_FCAT1-COL_POS = LX_FCATALOG-COL_POS.
         APPEND LX_FCAT1 TO T_FCAT1.
         CLEAR LX_FCAT1.
    ENDIF.
    ENDLOOP.
ENDLOOP.

It is possible to eliminate the nested loop here?
My goal is to overwrite the COL_POS from LX_FCATALOG to T_FCAT1 or LX_FCAT1
but the pre-requisite is to map it into correct field.
example:

T_FCAT1 OR LX_FCAT1.
FIELDNAME   COL_POS
EBELN          0


LT_FCATALOG OR LX_FCATALOG.
FIELDNAME    COL_POS
EBELN          23 <-----I want this to overwrite to T_FCAT1 OR LX_FCAT1.

[matt]

Looks to me like you've an endless loop (except where there are no shared FIELDNAME between the two internal tables), since you're looping through t_fcat1 you're adding new records into it.

[fedaros]

Seems no need of nested loop here. You can loop once T_FCAT1 assigning field symbol, as you want modify COL_POS, read table LT_FCATALOG per field and just set <fs_fcat1>-COL_POS = ls_fcatalog-COL_POS.

BTW: You have many questions unclosed, are it really without valid answers to be closed ?

[walkerist79]

@All two fieldcatalogs have different types.

[RaymondGiuseppi]

Try at least something such as

LOOP AT T_FCAT1 ASSIGNING <old>.
  READ TABLE T_FCATALOG WITH KEY FIELDNAME = <old>-FIELDNAME ASSIGNING <new>.     
  IF <new> IS ASSIGNED.
     <old>-COL_POS = <new>-COL_POS.
  ENDIF.
ENDLOOP.

What's your version?

[Sandra_Rossi]

I guess experience says there's no need to close the questions as people keep answering...

[Ryan-Crosby]

I stopped answering several months ago when it was obvious that the only thing that would continue was the flow of questions.