Help with timeout for select inside loop

Question

Hi everyone, im a little confused with this code. Can you help me to optimize it? Its giving Timeout dump.
Thanks so much, I´m new in abap and I tried hard, but its getting worse.
Any idea is welcomed.
LOOP AT it_lips.
    SELECT SINGLE *
      FROM vbak
     WHERE vbeln = it_lips-vgbel.
    IF sy-subrc <> 0 OR vbak-vbtyp <> 'C'.
      CONTINUE.
    ENDIF.
    SELECT SINGLE *
      FROM vbup
     WHERE vbeln = it_lips-vgbel
       AND posnr = it_lips-vgpos.
    IF sy-subrc = 0 AND vbup-lfgsa = 'C'.
      READ TABLE it_likp WITH KEY vbeln = it_lips-vbeln.
      IF it_likp-wadat < it_likp-wadat_ist.
        it_data-statu = 'N'.
        v_countn = v_countn + 1.
      ELSE.
        it_data-statu = 'S'.
        v_counts = v_counts + 1.
      ENDIF.
    ELSE.
      CONTINUE.
    ENDIF.
    it_data-vbeln = it_lips-vgbel.
    it_data-posnr = it_lips-vgpos.
    SELECT SINGLE matnr arktx kwmeng vrkme
      INTO (it_data-matnr, it_data-arktx, it_data-mengs, it_data-vrkme)
      FROM vbap
     WHERE vbeln = it_lips-vgbel
       AND posnr = it_lips-vgpos.
    it_data-menge = it_data-mengs.
    it_data-kunnr = vbak-kunnr.
    SELECT SINGLE name1
      INTO it_data-name1
      FROM kna1
     WHERE kunnr = it_data-kunnr.
    it_data-edatu = it_likp-wadat.
    it_data-wadat = it_likp-wadat_ist.
    it_data-vkorg = it_likp-vkorg.
    APPEND it_data.
    CLEAR: it_data, vbak, it_vbep, vbap, kna1, it_lips, it_likp.
  ENDLOOP.

Answer 1

The issue of SELECTing within a LOOP is much overblown. All of the SELECTs are SELECT SINGLE using the fully qualified primary key. Using a JOIN or FOR ALL ENTRIES might speed this up a bit, but dollars to doughnuts, the problem is here:
READ TABLE it_likp WITH KEY vbeln = it_lips-vbeln.
If it_likp is a standard table, you will be reading half of all of the entries, on average, every time you do the read. If you don't want to change it to a sorted or hashed table, SORT it_likp by vbeln before going into the loop and use the addition BINARY SEARCH on the READ statement.
Rob
Edited by: Rob Burbank on Apr 18, 2010 9:34 PM
Edited by: Rob Burbank on Apr 19, 2010 10:15 AM