Performance READ TABLE with Secondary Table Key Vs Binary Search

Secondary Table key

Access to an internal table using a secondary key is always optimized. This allows additional optimized keys to be introduced for sorted and hashed tables as well as optimized key accesses for standard tables.

• With Unique Sorted Key – Immediate update. Table key will be up to date
• With Non-Unique Sorted Key – Lazy update. Key will be update after first table access. Accessing same record 2^nd time is more faster.

https://help.sap.com/doc/abapdocu_751_index_htm/7.51/en-us/abenitab_key_secondary_update.htm

Binary Search

• We are using Binary search Instead linear search. Need to sort internal table before read

https://help.sap.com/doc/saphelp_nw70/7.0.31/en-US/fc/eb373d358411d1829f0000e829fbfe/content.htm?no_cache=true

Secondary Table key (WITH UNIQUE SORTED KEY) Vs Binary Search

REPORT  zperformance_test_uk.

DATA: lv_sta_time TYPE timestampl,
      lv_end_time TYPE timestampl,
      lv_diff_w   TYPE p DECIMALS 5,
      lv_diff_f   LIKE lv_diff_w.


PARAMETERS : p_count TYPE c LENGTH 10 OBLIGATORY.

START-OF-SELECTION.


  TYPES : BEGIN OF ty_vbrp,
            vbeln TYPE vbrp-vbeln,
            posnr TYPE vbrp-posnr,
            matnr TYPE vbrp-matnr,
          END OF ty_vbrp.

  DATA : lt_vbrp         TYPE STANDARD TABLE OF ty_vbrp.


  TYPES : BEGIN OF ty_mara,
            matnr TYPE vbrp-matnr,
          END OF ty_mara.

  DATA : lt_mara         TYPE STANDARD TABLE OF ty_mara,
         lt_mara_sec_key TYPE STANDARD TABLE OF ty_mara WITH UNIQUE SORTED KEY by_matnr COMPONENTS matnr.


  SELECT vbeln
         posnr
         matnr
         FROM vbrp
         INTO TABLE lt_vbrp
         UP TO p_count ROWS.

  IF lt_vbrp[] IS NOT INITIAL.

    SELECT matnr
           FROM mara
           INTO TABLE lt_mara.
*      Removed FOR ALL ENTRIES IN to get more data
*           FOR ALL ENTRIES IN lt_vbrp
*           WHERE matnr = lt_vbrp-matnr.
    lt_mara_sec_key = lt_mara.

  ENDIF.


  WRITE: /(50) 'WITH UNIQUE SORTED KEY'.

  DO 5 TIMES.

    GET TIME STAMP FIELD lv_sta_time.

    LOOP AT lt_vbrp ASSIGNING FIELD-SYMBOL(<fs_vbrp>).
      READ TABLE lt_mara_sec_key TRANSPORTING NO FIELDS WITH TABLE KEY by_matnr COMPONENTS matnr = <fs_vbrp>-matnr.
    ENDLOOP.


    GET TIME STAMP FIELD lv_end_time.

    lv_diff_w = lv_end_time - lv_sta_time.
    WRITE: /(30) 'Secondary Key', lv_diff_w.
    CLEAR : lv_diff_w, lv_end_time, lv_sta_time.

*******************************************************************************************************************
    GET TIME STAMP FIELD lv_sta_time.

    SORT lt_mara ASCENDING BY matnr.
    LOOP AT lt_vbrp ASSIGNING <fs_vbrp>.
      READ TABLE lt_mara TRANSPORTING NO FIELDS WITH KEY matnr = <fs_vbrp>-matnr
                                           BINARY SEARCH.
    ENDLOOP.


    GET TIME STAMP FIELD lv_end_time.

    lv_diff_w = lv_end_time - lv_sta_time.
    WRITE: /(30) 'Binary Search', lv_diff_w.
    CLEAR : lv_diff_w, lv_end_time, lv_sta_time.
    WRITE: /(30) '----------------------------'.

  ENDDO.

Results:

Immediate update. Table Secondary key is faster

Secondary Table key (WITH NON-UNIQUE SORTED KEY) Vs Binary Search

REPORT  zperformance_test_uk.

DATA: lv_sta_time TYPE timestampl,
      lv_end_time TYPE timestampl,
      lv_diff_w   TYPE p DECIMALS 5,
      lv_diff_f   LIKE lv_diff_w.


PARAMETERS : p_count TYPE c LENGTH 10 OBLIGATORY.

START-OF-SELECTION.


  TYPES : BEGIN OF ty_vbrp,
            vbeln TYPE vbrp-vbeln,
            posnr TYPE vbrp-posnr,
            matnr TYPE vbrp-matnr,
          END OF ty_vbrp.

  DATA : lt_vbrp         TYPE STANDARD TABLE OF ty_vbrp.


  TYPES : BEGIN OF ty_mara,
            matnr TYPE vbrp-matnr,
          END OF ty_mara.

  DATA : lt_mara         TYPE STANDARD TABLE OF ty_mara,
         lt_mara_sec_key TYPE STANDARD TABLE OF ty_mara WITH NON-UNIQUE SORTED KEY by_matnr COMPONENTS matnr.


  SELECT vbeln
         posnr
         matnr
         FROM vbrp
         INTO TABLE lt_vbrp
         UP TO p_count ROWS.

  IF lt_vbrp[] IS NOT INITIAL.

    SELECT matnr
           FROM mara
           INTO TABLE lt_mara.
*      Removed FOR ALL ENTRIES IN to get more data
*           FOR ALL ENTRIES IN lt_vbrp
*           WHERE matnr = lt_vbrp-matnr.
    lt_mara_sec_key = lt_mara.

  ENDIF.


  WRITE: /(50) 'WITH UNIQUE SORTED KEY'.

  DO 5 TIMES.

    GET TIME STAMP FIELD lv_sta_time.

    LOOP AT lt_vbrp ASSIGNING FIELD-SYMBOL(<fs_vbrp>).
      READ TABLE lt_mara_sec_key TRANSPORTING NO FIELDS WITH TABLE KEY by_matnr COMPONENTS matnr = <fs_vbrp>-matnr.
    ENDLOOP.


    GET TIME STAMP FIELD lv_end_time.

    lv_diff_w = lv_end_time - lv_sta_time.
    WRITE: /(30) 'Secondary Key', lv_diff_w.
    CLEAR : lv_diff_w, lv_end_time, lv_sta_time.

*******************************************************************************************************************
    GET TIME STAMP FIELD lv_sta_time.

    SORT lt_mara ASCENDING BY matnr.
    LOOP AT lt_vbrp ASSIGNING <fs_vbrp>.
      READ TABLE lt_mara TRANSPORTING NO FIELDS WITH KEY matnr = <fs_vbrp>-matnr
                                           BINARY SEARCH.
    ENDLOOP.


    GET TIME STAMP FIELD lv_end_time.

    lv_diff_w = lv_end_time - lv_sta_time.
    WRITE: /(30) 'Binary Search', lv_diff_w.
    CLEAR : lv_diff_w, lv_end_time, lv_sta_time.
    WRITE: /(30) '----------------------------'.

  ENDDO.

Results

Secondary key is lazy update. First time binary search faster. Second Onward time secondary key is faster.