There would have been many instances where we would have to process large entries in an internal table with a WHERE condition. This article is intended to demonstrate the comparison between three different methods in handling this situation.
First Method: The normal method used by most of us. Standard internal table processing using WHERE condition
Second Method: Same as above, but here we would be using the Sorted table
Third Method: Sorted table and using the Index
Following is the demo program illustrating the above three methods:
REPORT ZINTERNAL_TABLE_OPERATIONS.
* Program to find the best method in reading the internal tables
* Author: Suresh Kumar Parvathaneni
* Type declaration
TYPES:
BEGIN OF TY_MARA,
MATNR LIKE MARA-MATNR,
MTART LIKE MARA-MTART,
END OF TY_MARA.
* Internal table declaration
DATA:
T_MARA TYPE STANDARD TABLE OF TY_MARA,
T_MARA1 TYPE SORTED TABLE OF TY_MARA
WITH NON-UNIQUE KEY MTART.
* Variable declaration
DATA:
W_COUNTER TYPE I,
W_RUNTIME1 TYPE I,
W_RUNTIME2 TYPE I,
W_TABIX LIKE SY-TABIX.
* Table workarea definition
DATA:
WA_MARA TYPE TY_MARA.
SELECT MATNR " Material Number
MTART " Material Type
FROM MARA
INTO TABLE T_MARA.
T_MARA1[] = T_MARA[].
* CASE 1: Processing internal table using LOOP..WHERE Condition
GET RUN TIME FIELD W_RUNTIME1.
LOOP AT T_MARA INTO WA_MARA WHERE MTART EQ 'FHMI'.
ADD 1 TO W_COUNTER.
ENDLOOP.
GET RUN TIME FIELD W_RUNTIME2.
* Calculate Runtime
W_RUNTIME2 = W_RUNTIME2 - W_RUNTIME1.
WRITE W_RUNTIME2.
CLEAR W_COUNTER.
* CASE 2: Using a Sorted table
GET RUN TIME FIELD W_RUNTIME1.
LOOP AT T_MARA1 INTO WA_MARA WHERE MTART EQ 'FHMI'.
ADD 1 TO W_COUNTER.
ENDLOOP.
GET RUN TIME FIELD W_RUNTIME2.
* Calculate Runtime
W_RUNTIME2 = W_RUNTIME2 - W_RUNTIME1.
WRITE W_RUNTIME2.
CLEAR W_COUNTER.
* CASE 3: Using INDEX on a sorted table
GET RUN TIME FIELD W_RUNTIME1.
READ TABLE T_MARA1 INTO WA_MARA WITH KEY MTART = 'FHMI'.
IF SY-SUBRC EQ 0.
W_TABIX = SY-TABIX + 1.
ADD 1 TO W_COUNTER.
LOOP AT T_MARA1 INTO WA_MARA FROM W_TABIX.
IF WA_MARA-MTART NE 'FHMI'.
EXIT.
ENDIF.
ADD 1 TO W_COUNTER.
ENDLOOP.
ENDIF.
GET RUN TIME FIELD W_RUNTIME2.
* Calculate Runtime
W_RUNTIME2 = W_RUNTIME2 - W_RUNTIME1.
WRITE W_RUNTIME2.
Following is the analysis report in microseconds, as per the data volume:
Records: 21,390
Iteration No
|
Using
|
Using Sorted table LOOP & WHERE
|
Using INDEX on Sorted table
|
1
|
897
|
887
|
11
|
2
|
839
|
879
|
10
|
3
|
839
|
877
|
10
|
4
|
834
|
880
|
9
|
5
|
842
|
837
|
10
|
Records: 132,693
Iteration No
|
Using
|
Using Sorted table LOOP & WHERE
|
Using INDEX on Sorted table
|
1
|
34239
|
35774
|
3567
|
2
|
34271
|
38250
|
3592
|
3
|
34492
|
36534
|
3554
|
4
|
34198
|
35695
|
3584
|
Sorted table might have given a better performance here if the field in the WHERE condition is the first field in the internal table. However, from the above statistics, we can say that method 3 is better than the other 2 methods. In production environment, the data would be huge and the performance could be much improved with this simple technique.
Thanks to: Suresh Kumar Parvathaneni
