从内部表中抽取唯一记录的方法测试

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2006-06-21

三种方法简单介绍:

方法一: 内部表循环赋值,使用COLLECT语句追加记录

方法二: 内部表循环赋值,使用AT NEW和APPEND语句追加记录

方法三: 整个内部表赋值,使用DELETE ADJACENT DUPLICATES语句删除重复记录

运行10次结果如下:

方法一	方法二	方法三
48,139	68,657	8,830
45,230	68,474	8,789
44,751	68,553	8,779
44,771	68,523	8,777
44,775	68,441	8,761
44,777	68,525	8,780
45,422	69,461	9,318
45,367	68,404	8,773
44,743	68,389	8,771
44,871	68,400	9,183

运行结果分析:

数据说明一切,我就不多说了.

程序代码

REPORT z_xam_temp3 .

DATA: t1 TYPE i,
      t2 TYPE i,
      times TYPE i.

TABLES: marc.

DATA: BEGIN OF it_marc OCCURS 0,
        matnr LIKE marc-matnr,
        werks LIKE marc-werks,
      END OF it_marc.

DATA: BEGIN OF it_mara OCCURS 0,
        matnr LIKE mara-matnr,
      END OF it_mara.

SELECT matnr werks
INTO TABLE it_marc
FROM marc
WHERE werks = '1005'.

DO 10 TIMES.
  REFRESH it_mara.

* METHOD 1
  GET RUN TIME FIELD t1.
  LOOP AT it_marc.
    CLEAR it_mara.
    it_mara-matnr = it_marc-matnr.
    COLLECT it_mara.
  ENDLOOP.
  GET RUN TIME FIELD t2.
  times = t2 - t1.
  WRITE: AT /1 times.

* METHOD 2
  GET RUN TIME FIELD t1.
*  SORT it_mara BY matnr.
  LOOP AT it_marc.
    AT NEW matnr.
      CLEAR it_mara.
      it_mara-matnr = it_marc-matnr.
      APPEND it_mara.
    ENDAT.
  ENDLOOP.
  GET RUN TIME FIELD t2.
  times = t2 - t1.
  WRITE: times.

* METHOD 3:
  GET RUN TIME FIELD t1.
  it_mara[] = it_marc[].
*  SORT it_mara BY matnr.
  DELETE ADJACENT DUPLICATES FROM it_mara
    COMPARING matnr.

  GET RUN TIME FIELD t2.
  times = t2 - t1.
  WRITE: times.

  NEW-LINE.
ENDDO.