STANDARD, SORTED和HASHED Table在READ数据时性能比较分析

1、程序代码：

1. TYPES:
   
2.   BEGIN OF ty_vbpa,
   
3.     vbeln TYPE vbpa-vbeln,
   
4.     posnr TYPE vbpa-posnr,
   
5.     parvw TYPE vbpa-parvw,
   
6.     kunnr TYPE vbpa-kunnr,
   
7.   END  OF ty_vbpa.
   
8. 
   
9. DATA: t_std    TYPE STANDARD TABLE OF ty_vbpa.
   
10. DATA: t_sorted TYPE SORTED TABLE OF ty_vbpa WITH UNIQUE KEY vbeln.
    
11. DATA: t_hashed TYPE HASHED TABLE OF ty_vbpa WITH UNIQUE KEY vbeln.
    
12. 
    
13. TYPES:
    
14.   BEGIN OF ty_vbak,
    
15.     vbeln TYPE vbak-vbeln,
    
16.     found TYPE flag,
    
17.   END   OF ty_vbak.
    
18. DATA: t_vbak TYPE STANDARD TABLE OF ty_vbak.
    
19. DATA: lt_vbak TYPE STANDARD TABLE OF ty_vbak.
    
20. FIELD-SYMBOLS: <lfs_vbak> LIKE LINE OF t_vbak.
    
21. 
    
22. DATA: lv_flag TYPE flag,
    
23.       lv_sta_time TYPE timestampl,
    
24.       lv_end_time TYPE timestampl,
    
25.       lv_diff   TYPE p DECIMALS 5.
    
26. 
    
27. DATA: lv_num_main TYPE i,
    
28.       lv_num_sub TYPE i.
    
29. 
    
30. START-OF-SELECTION.
    
31.   lv_num_main = 50000.            " Change for different number of records
    
32.   lv_num_sub = lv_num_main / 2.
    
33. *
    
34.   SELECT vbeln
    
35.     FROM vbak
    
36.     INTO TABLE t_vbak
    
37.     UP TO lv_num_main ROWS.
    
38. *
    
39.   SELECT vbeln posnr parvw kunnr
    
40.     INTO TABLE t_std
    
41.     FROM vbpa
    
42.     UP TO lv_num_sub ROWS
    
43.     FOR ALL ENTRIES IN t_vbak
    
44.     WHERE vbeln = t_vbak-vbeln
    
45.     AND   parvw = 'AG'.
    
46. 
    
47. * Copying into the Sorted and Hashed table
    
48.   t_sorted = t_std.
    
49.   t_hashed = t_std.
    
50. *----
    
51. * READ on Standard Table
    
52.   GET TIME STAMP FIELD lv_sta_time.
    
53.   LOOP AT t_vbak ASSIGNING <lfs_vbak>.
    
54.     READ TABLE t_std TRANSPORTING NO FIELDS
    
55.       WITH KEY vbeln = <lfs_vbak>-vbeln.
    
56.     IF sy-subrc EQ 0.
    
57.       "..
    
58.     ENDIF.
    
59.   ENDLOOP.
    
60.   GET TIME STAMP FIELD lv_end_time.
    
61.   lv_diff  = lv_end_time - lv_sta_time.
    
62.   WRITE: /(30) 'Standard Table', lv_diff.
    
63. *
    
64. *----
    
65. * READ on Standard table with Binary Search
    
66.   GET TIME STAMP FIELD lv_sta_time.
    
67.   SORT t_std BY vbeln.
    
68.   LOOP AT t_vbak ASSIGNING <lfs_vbak>.
    
69.     READ TABLE t_std TRANSPORTING NO FIELDS
    
70.       WITH KEY vbeln = <lfs_vbak>-vbeln
    
71.       BINARY SEARCH.
    
72.     IF sy-subrc EQ 0.
    
73.       "..
    
74.     ENDIF.
    
75.   ENDLOOP.
    
76.   GET TIME STAMP FIELD lv_end_time.
    
77.   lv_diff  = lv_end_time - lv_sta_time.
    
78.   WRITE: /(30) 'Standard Table - Binary', lv_diff.
    
79. *
    
80. *----
    
81. * READ on Sorted Table
    
82.   GET TIME STAMP FIELD lv_sta_time.
    
83.   LOOP AT t_vbak ASSIGNING <lfs_vbak>.
    
84.     READ TABLE t_sorted TRANSPORTING NO FIELDS
    
85.       WITH KEY vbeln = <lfs_vbak>-vbeln.
    
86.     IF sy-subrc EQ 0.
    
87.       "..
    
88.     ENDIF.
    
89.   ENDLOOP.
    
90.   GET TIME STAMP FIELD lv_end_time.
    
91.   lv_diff  = lv_end_time - lv_sta_time.
    
92.   WRITE: /(30) 'Sorted Table', lv_diff.
    
93. *
    
94. *----
    
95. * READ on HASHED table
    
96.   GET TIME STAMP FIELD lv_sta_time.
    
97.   LOOP AT t_vbak ASSIGNING <lfs_vbak>.
    
98.     READ TABLE t_hashed TRANSPORTING NO FIELDS
    
99.       WITH TABLE KEY vbeln = <lfs_vbak>-vbeln.
    
100.     IF sy-subrc EQ 0.
     
101.       "..
     
102.     ENDIF.
     
103.   ENDLOOP.
     
104.   GET TIME STAMP FIELD lv_end_time.
     
105.   lv_diff  = lv_end_time - lv_sta_time.
     
106.   WRITE: /(30) 'Hashed Table', lv_diff.

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2、测试结果：

排除STANDARD TABLE读数前的排序，STANDARD TABLE使用read Binary和SORTED TABLE读数时几乎效差不多，但是HASHED Table性能几乎是STANDARD TABLE的两倍，所以内表数据较大时，建议选择Hashed Table