Sorted table



Sorted tables

This is the most appropriate type if you need a table which is sorted as you fill it. You fill sorted tables using the INSERT statement. Entries are inserted according to the sort sequence defined through the table key. Any illegal entries are recognized as soon as you try to add them to the table. The response time for key access is logarithmically proportional to the number of table entries, since the system always uses a binary search. Sorted tables are particularly useful for partially sequential processing in a LOOP if you specify the beginning of the table key in the WHERE condition.

Using Sorted table and Index while processing Internal tables

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

• 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 MATNR 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 ConditionGET 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 tableGET 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 tableGET 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 Normal LOOP & WHERE

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 Normal LOOP & WHERE

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.