Application Development Discussions
Join the discussions or start your own on all things application development, including tools and APIs, programming models, and keeping your skills sharp.
cancel
Showing results for 
Search instead for 
Did you mean: 

Performance improvement

vinod_vemuru2
Active Contributor
0 Kudos

Hi Guys,

Is there any chance of improving the performance of these two select queries. This will be running in both fore ground and back ground. No chance of giving Material numbers. We will always exclude materials that starts with M(Exclude M*). User is getting timed out error if he run this report for 2 weeks in production.

SELECT objectclas objectid changenr username udate utime

planchngnr act_chngno change_ind

INTO TABLE i_cdhdr

FROM cdhdr

WHERE objectclas EQ c_mat

AND objectid IN so_matnr

AND udate IN so_udate.

IF NOT i_cdhdr[] IS INITIAL.

SORT i_cdhdr BY objectclas objectid changenr.

SELECT objectclas objectid changenr tabname tabkey fname

chngind text_case

INTO TABLE i_cdpos

FROM cdpos

FOR ALL ENTRIES IN i_cdhdr

WHERE objectclas EQ i_cdhdr-objectclas

AND objectid EQ i_cdhdr-objectid

AND changenr EQ i_cdhdr-changenr

AND tabname EQ c_mvke

AND fname EQ c_key

AND chngind IN (c_i, c_d).

ENDIF.

c_mat- 'MATERIAL'

so_matnr- Exclude M*

so_udate- Date range(Probably 2 weeks)

c_mvke- 'MVKE'

c_key-'KEY'

c_i-'I'

c_d-'D'.

Please let me know some solution for this. Also is there any function module available to get the above data. I am using 4.6C version.

Thanks in Advance,

Vinod.

1 ACCEPTED SOLUTION

Former Member
0 Kudos

Ways of Performance Tuning

1. Selection Criteria

2. Select Statements

• Select Queries

• SQL Interface

• Aggregate Functions

• For all Entries

Select Over more than one internal table

Selection Criteria

1. Restrict the data to the selection criteria itself, rather than filtering it out using the ABAP code using CHECK statement.

2. Select with selection list.

SELECT * FROM SBOOK INTO SBOOK_WA.

CHECK: SBOOK_WA-CARRID = 'LH' AND

SBOOK_WA-CONNID = '0400'.

ENDSELECT.

The above code can be much more optimized by the code written below which avoids CHECK, selects with selection list

SELECT CARRID CONNID FLDATE BOOKID FROM SBOOK INTO TABLE T_SBOOK

WHERE SBOOK_WA-CARRID = 'LH' AND

SBOOK_WA-CONNID = '0400'.

Select Statements Select Queries

1. Avoid nested selects

SELECT * FROM EKKO INTO EKKO_WA.

SELECT * FROM EKAN INTO EKAN_WA

WHERE EBELN = EKKO_WA-EBELN.

ENDSELECT.

ENDSELECT.

The above code can be much more optimized by the code written below.

SELECT PF1 PF2 FF3 FF4 INTO TABLE ITAB

FROM EKKO AS P INNER JOIN EKAN AS F

ON PEBELN = FEBELN.

Note: A simple SELECT loop is a single database access whose result is passed to the ABAP program line by line. Nested SELECT loops mean that the number of accesses in the inner loop is multiplied by the number of accesses in the outer loop. One should therefore use nested SELECT loops only if the selection in the outer loop contains very few lines or the outer loop is a SELECT SINGLE statement.

2. Select all the records in a single shot using into table clause of select statement rather than to use Append statements.

SELECT * FROM SBOOK INTO SBOOK_WA.

CHECK: SBOOK_WA-CARRID = 'LH' AND

SBOOK_WA-CONNID = '0400'.

ENDSELECT.

The above code can be much more optimized by the code written below which avoids CHECK, selects with selection list and puts the data in one shot using into table

SELECT CARRID CONNID FLDATE BOOKID FROM SBOOK INTO TABLE T_SBOOK

WHERE SBOOK_WA-CARRID = 'LH' AND

SBOOK_WA-CONNID = '0400'.

3. When a base table has multiple indices, the where clause should be in the order of the index, either a primary or a secondary index.

To choose an index, the optimizer checks the field names specified in the where clause and then uses an index that has the same order of the fields. In certain scenarios, it is advisable to check whether a new index can speed up the performance of a program. This will come handy in programs that access data from the finance tables.

4. For testing existence, use Select.. Up to 1 rows statement instead of a Select-Endselect-loop with an Exit.

SELECT * FROM SBOOK INTO SBOOK_WA

UP TO 1 ROWS

WHERE CARRID = 'LH'.

ENDSELECT.

The above code is more optimized as compared to the code mentioned below for testing existence of a record.

SELECT * FROM SBOOK INTO SBOOK_WA

WHERE CARRID = 'LH'.

EXIT.

ENDSELECT.

5. Use Select Single if all primary key fields are supplied in the Where condition .

If all primary key fields are supplied in the Where conditions you can even use Select Single.

Select Single requires one communication with the database system, whereas Select-Endselect needs two.

Select Statements SQL Interface

1. Use column updates instead of single-row updates

to update your database tables.

SELECT * FROM SFLIGHT INTO SFLIGHT_WA.

SFLIGHT_WA-SEATSOCC =

SFLIGHT_WA-SEATSOCC - 1.

UPDATE SFLIGHT FROM SFLIGHT_WA.

ENDSELECT.

The above mentioned code can be more optimized by using the following code

UPDATE SFLIGHT

SET SEATSOCC = SEATSOCC - 1.

2. For all frequently used Select statements, try to use an index.

SELECT * FROM SBOOK CLIENT SPECIFIED INTO SBOOK_WA

WHERE CARRID = 'LH'

AND CONNID = '0400'.

ENDSELECT.

The above mentioned code can be more optimized by using the following code

SELECT * FROM SBOOK CLIENT SPECIFIED INTO SBOOK_WA

WHERE MANDT IN ( SELECT MANDT FROM T000 )

AND CARRID = 'LH'

AND CONNID = '0400'.

ENDSELECT.

3. Using buffered tables improves the performance considerably.

Bypassing the buffer increases the network considerably

SELECT SINGLE * FROM T100 INTO T100_WA

BYPASSING BUFFER

WHERE SPRSL = 'D'

AND ARBGB = '00'

AND MSGNR = '999'.

The above mentioned code can be more optimized by using the following code

SELECT SINGLE * FROM T100 INTO T100_WA

WHERE SPRSL = 'D'

AND ARBGB = '00'

AND MSGNR = '999'.

Select Statements Aggregate Functions

• If you want to find the maximum, minimum, sum and average value or the count of a database column, use a select list with aggregate functions instead of computing the aggregates yourself.

Some of the Aggregate functions allowed in SAP are MAX, MIN, AVG, SUM, COUNT, COUNT( * )

Consider the following extract.

Maxno = 0.

Select * from zflight where airln = ‘LF’ and cntry = ‘IN’.

Check zflight-fligh > maxno.

Maxno = zflight-fligh.

Endselect.

The above mentioned code can be much more optimized by using the following code.

Select max( fligh ) from zflight into maxno where airln = ‘LF’ and cntry = ‘IN’.

Select Statements For All Entries

• The for all entries creates a where clause, where all the entries in the driver table are combined with OR. If the number of entries in the driver table is larger than rsdb/max_blocking_factor, several similar SQL statements are executed to limit the length of the WHERE clause.

The plus

• Large amount of data

• Mixing processing and reading of data

• Fast internal reprocessing of data

• Fast

The Minus

• Difficult to program/understand

• Memory could be critical (use FREE or PACKAGE size)

Points to be must considered FOR ALL ENTRIES

• Check that data is present in the driver table

• Sorting the driver table

• Removing duplicates from the driver table

Consider the following piece of extract

Loop at int_cntry.

Select single * from zfligh into int_fligh

where cntry = int_cntry-cntry.

Append int_fligh.

Endloop.

The above mentioned can be more optimized by using the following code.

Sort int_cntry by cntry.

Delete adjacent duplicates from int_cntry.

If NOT int_cntry[] is INITIAL.

Select * from zfligh appending table int_fligh

For all entries in int_cntry

Where cntry = int_cntry-cntry.

Endif.

Select Statements Select Over more than one Internal table

1. Its better to use a views instead of nested Select statements.

SELECT * FROM DD01L INTO DD01L_WA

WHERE DOMNAME LIKE 'CHAR%'

AND AS4LOCAL = 'A'.

SELECT SINGLE * FROM DD01T INTO DD01T_WA

WHERE DOMNAME = DD01L_WA-DOMNAME

AND AS4LOCAL = 'A'

AND AS4VERS = DD01L_WA-AS4VERS

AND DDLANGUAGE = SY-LANGU.

ENDSELECT.

The above code can be more optimized by extracting all the data from view DD01V_WA

SELECT * FROM DD01V INTO DD01V_WA

WHERE DOMNAME LIKE 'CHAR%'

AND DDLANGUAGE = SY-LANGU.

ENDSELECT

2. To read data from several logically connected tables use a join instead of nested Select statements. Joins are preferred only if all the primary key are available in WHERE clause for the tables that are joined. If the primary keys are not provided in join the Joining of tables itself takes time.

SELECT * FROM EKKO INTO EKKO_WA.

SELECT * FROM EKAN INTO EKAN_WA

WHERE EBELN = EKKO_WA-EBELN.

ENDSELECT.

ENDSELECT.

The above code can be much more optimized by the code written below.

SELECT PF1 PF2 FF3 FF4 INTO TABLE ITAB

FROM EKKO AS P INNER JOIN EKAN AS F

ON PEBELN = FEBELN.

3. Instead of using nested Select loops it is often better to use subqueries.

SELECT * FROM SPFLI

INTO TABLE T_SPFLI

WHERE CITYFROM = 'FRANKFURT'

AND CITYTO = 'NEW YORK'.

SELECT * FROM SFLIGHT AS F

INTO SFLIGHT_WA

FOR ALL ENTRIES IN T_SPFLI

WHERE SEATSOCC < F~SEATSMAX

AND CARRID = T_SPFLI-CARRID

AND CONNID = T_SPFLI-CONNID

AND FLDATE BETWEEN '19990101' AND '19990331'.

ENDSELECT.

The above mentioned code can be even more optimized by using subqueries instead of for all entries.

SELECT * FROM SFLIGHT AS F INTO SFLIGHT_WA

WHERE SEATSOCC < F~SEATSMAX

AND EXISTS ( SELECT * FROM SPFLI

WHERE CARRID = F~CARRID

AND CONNID = F~CONNID

AND CITYFROM = 'FRANKFURT'

AND CITYTO = 'NEW YORK' )

AND FLDATE BETWEEN '19990101' AND '19990331'.

ENDSELECT.

1. Table operations should be done using explicit work areas rather than via header lines.

READ TABLE ITAB INTO WA WITH KEY K = 'X‘ BINARY SEARCH.

IS MUCH FASTER THAN USING

READ TABLE ITAB INTO WA WITH KEY K = 'X'.

If TAB has n entries, linear search runs in O( n ) time, whereas binary search takes only O( log2( n ) ).

2. Always try to use binary search instead of linear search. But don’t forget to sort your internal table before that.

READ TABLE ITAB INTO WA WITH KEY K = 'X'. IS FASTER THAN USING

READ TABLE ITAB INTO WA WITH KEY (NAME) = 'X'.

3. A dynamic key access is slower than a static one, since the key specification must be evaluated at runtime.

4. A binary search using secondary index takes considerably less time.

5. LOOP ... WHERE is faster than LOOP/CHECK because LOOP ... WHERE evaluates the specified condition internally.

LOOP AT ITAB INTO WA WHERE K = 'X'.

" ...

ENDLOOP.

The above code is much faster than using

LOOP AT ITAB INTO WA.

CHECK WA-K = 'X'.

" ...

ENDLOOP.

6. Modifying selected components using “ MODIFY itab …TRANSPORTING f1 f2.. “ accelerates the task of updating a line of an internal table.

WA-DATE = SY-DATUM.

MODIFY ITAB FROM WA INDEX 1 TRANSPORTING DATE.

The above code is more optimized as compared to

WA-DATE = SY-DATUM.

MODIFY ITAB FROM WA INDEX 1.

7. Accessing the table entries directly in a "LOOP ... ASSIGNING ..." accelerates the task of updating a set of lines of an internal table considerably

Modifying selected components only makes the program faster as compared to Modifying all lines completely.

e.g,

LOOP AT ITAB ASSIGNING <WA>.

I = SY-TABIX MOD 2.

IF I = 0.

<WA>-FLAG = 'X'.

ENDIF.

ENDLOOP.

The above code works faster as compared to

LOOP AT ITAB INTO WA.

I = SY-TABIX MOD 2.

IF I = 0.

WA-FLAG = 'X'.

MODIFY ITAB FROM WA.

ENDIF.

ENDLOOP.

8. If collect semantics is required, it is always better to use to COLLECT rather than READ BINARY and then ADD.

LOOP AT ITAB1 INTO WA1.

READ TABLE ITAB2 INTO WA2 WITH KEY K = WA1-K BINARY SEARCH.

IF SY-SUBRC = 0.

ADD: WA1-VAL1 TO WA2-VAL1,

WA1-VAL2 TO WA2-VAL2.

MODIFY ITAB2 FROM WA2 INDEX SY-TABIX TRANSPORTING VAL1 VAL2.

ELSE.

INSERT WA1 INTO ITAB2 INDEX SY-TABIX.

ENDIF.

ENDLOOP.

The above code uses BINARY SEARCH for collect semantics. READ BINARY runs in O( log2(n) ) time. The above piece of code can be more optimized by

LOOP AT ITAB1 INTO WA.

COLLECT WA INTO ITAB2.

ENDLOOP.

SORT ITAB2 BY K.

COLLECT, however, uses a hash algorithm and is therefore independent

of the number of entries (i.e. O(1)) .

9. "APPEND LINES OF itab1 TO itab2" accelerates the task of appending a table to another table considerably as compared to “ LOOP-APPEND-ENDLOOP.”

APPEND LINES OF ITAB1 TO ITAB2.

This is more optimized as compared to

LOOP AT ITAB1 INTO WA.

APPEND WA TO ITAB2.

ENDLOOP.

10. “DELETE ADJACENT DUPLICATES“ accelerates the task of deleting duplicate entries considerably as compared to “ READ-LOOP-DELETE-ENDLOOP”.

DELETE ADJACENT DUPLICATES FROM ITAB COMPARING K.

This is much more optimized as compared to

READ TABLE ITAB INDEX 1 INTO PREV_LINE.

LOOP AT ITAB FROM 2 INTO WA.

IF WA = PREV_LINE.

DELETE ITAB.

ELSE.

PREV_LINE = WA.

ENDIF.

ENDLOOP.

11. "DELETE itab FROM ... TO ..." accelerates the task of deleting a sequence of lines considerably as compared to “ DO -DELETE-ENDDO”.

DELETE ITAB FROM 450 TO 550.

This is much more optimized as compared to

DO 101 TIMES.

DELETE ITAB INDEX 450.

ENDDO.

12. Copying internal tables by using “ITAB2[ ] = ITAB1[ ]” as compared to “LOOP-APPEND-ENDLOOP”.

ITAB2[] = ITAB1[].

This is much more optimized as compared to

REFRESH ITAB2.

LOOP AT ITAB1 INTO WA.

APPEND WA TO ITAB2.

ENDLOOP.

13. Specify the sort key as restrictively as possible to run the program faster.

“SORT ITAB BY K.” makes the program runs faster as compared to “SORT ITAB.”

Internal Tables contd…

Hashed and Sorted tables

1. For single read access hashed tables are more optimized as compared to sorted tables.

2. For partial sequential access sorted tables are more optimized as compared to hashed tables

Hashed And Sorted Tables

Point # 1

Consider the following example where HTAB is a hashed table and STAB is a sorted table

DO 250 TIMES.

N = 4 * SY-INDEX.

READ TABLE HTAB INTO WA WITH TABLE KEY K = N.

IF SY-SUBRC = 0.

" ...

ENDIF.

ENDDO.

This runs faster for single read access as compared to the following same code for sorted table

DO 250 TIMES.

N = 4 * SY-INDEX.

READ TABLE STAB INTO WA WITH TABLE KEY K = N.

IF SY-SUBRC = 0.

" ...

ENDIF.

ENDDO.

Point # 2

Similarly for Partial Sequential access the STAB runs faster as compared to HTAB

LOOP AT STAB INTO WA WHERE K = SUBKEY.

" ...

ENDLOOP.

This runs faster as compared to

LOOP AT HTAB INTO WA WHERE K = SUBKEY.

" ...

ENDLOOP.

8 REPLIES 8

Former Member
0 Kudos

Ways of Performance Tuning

1. Selection Criteria

2. Select Statements

• Select Queries

• SQL Interface

• Aggregate Functions

• For all Entries

Select Over more than one internal table

Selection Criteria

1. Restrict the data to the selection criteria itself, rather than filtering it out using the ABAP code using CHECK statement.

2. Select with selection list.

SELECT * FROM SBOOK INTO SBOOK_WA.

CHECK: SBOOK_WA-CARRID = 'LH' AND

SBOOK_WA-CONNID = '0400'.

ENDSELECT.

The above code can be much more optimized by the code written below which avoids CHECK, selects with selection list

SELECT CARRID CONNID FLDATE BOOKID FROM SBOOK INTO TABLE T_SBOOK

WHERE SBOOK_WA-CARRID = 'LH' AND

SBOOK_WA-CONNID = '0400'.

Select Statements Select Queries

1. Avoid nested selects

SELECT * FROM EKKO INTO EKKO_WA.

SELECT * FROM EKAN INTO EKAN_WA

WHERE EBELN = EKKO_WA-EBELN.

ENDSELECT.

ENDSELECT.

The above code can be much more optimized by the code written below.

SELECT PF1 PF2 FF3 FF4 INTO TABLE ITAB

FROM EKKO AS P INNER JOIN EKAN AS F

ON PEBELN = FEBELN.

Note: A simple SELECT loop is a single database access whose result is passed to the ABAP program line by line. Nested SELECT loops mean that the number of accesses in the inner loop is multiplied by the number of accesses in the outer loop. One should therefore use nested SELECT loops only if the selection in the outer loop contains very few lines or the outer loop is a SELECT SINGLE statement.

2. Select all the records in a single shot using into table clause of select statement rather than to use Append statements.

SELECT * FROM SBOOK INTO SBOOK_WA.

CHECK: SBOOK_WA-CARRID = 'LH' AND

SBOOK_WA-CONNID = '0400'.

ENDSELECT.

The above code can be much more optimized by the code written below which avoids CHECK, selects with selection list and puts the data in one shot using into table

SELECT CARRID CONNID FLDATE BOOKID FROM SBOOK INTO TABLE T_SBOOK

WHERE SBOOK_WA-CARRID = 'LH' AND

SBOOK_WA-CONNID = '0400'.

3. When a base table has multiple indices, the where clause should be in the order of the index, either a primary or a secondary index.

To choose an index, the optimizer checks the field names specified in the where clause and then uses an index that has the same order of the fields. In certain scenarios, it is advisable to check whether a new index can speed up the performance of a program. This will come handy in programs that access data from the finance tables.

4. For testing existence, use Select.. Up to 1 rows statement instead of a Select-Endselect-loop with an Exit.

SELECT * FROM SBOOK INTO SBOOK_WA

UP TO 1 ROWS

WHERE CARRID = 'LH'.

ENDSELECT.

The above code is more optimized as compared to the code mentioned below for testing existence of a record.

SELECT * FROM SBOOK INTO SBOOK_WA

WHERE CARRID = 'LH'.

EXIT.

ENDSELECT.

5. Use Select Single if all primary key fields are supplied in the Where condition .

If all primary key fields are supplied in the Where conditions you can even use Select Single.

Select Single requires one communication with the database system, whereas Select-Endselect needs two.

Select Statements SQL Interface

1. Use column updates instead of single-row updates

to update your database tables.

SELECT * FROM SFLIGHT INTO SFLIGHT_WA.

SFLIGHT_WA-SEATSOCC =

SFLIGHT_WA-SEATSOCC - 1.

UPDATE SFLIGHT FROM SFLIGHT_WA.

ENDSELECT.

The above mentioned code can be more optimized by using the following code

UPDATE SFLIGHT

SET SEATSOCC = SEATSOCC - 1.

2. For all frequently used Select statements, try to use an index.

SELECT * FROM SBOOK CLIENT SPECIFIED INTO SBOOK_WA

WHERE CARRID = 'LH'

AND CONNID = '0400'.

ENDSELECT.

The above mentioned code can be more optimized by using the following code

SELECT * FROM SBOOK CLIENT SPECIFIED INTO SBOOK_WA

WHERE MANDT IN ( SELECT MANDT FROM T000 )

AND CARRID = 'LH'

AND CONNID = '0400'.

ENDSELECT.

3. Using buffered tables improves the performance considerably.

Bypassing the buffer increases the network considerably

SELECT SINGLE * FROM T100 INTO T100_WA

BYPASSING BUFFER

WHERE SPRSL = 'D'

AND ARBGB = '00'

AND MSGNR = '999'.

The above mentioned code can be more optimized by using the following code

SELECT SINGLE * FROM T100 INTO T100_WA

WHERE SPRSL = 'D'

AND ARBGB = '00'

AND MSGNR = '999'.

Select Statements Aggregate Functions

• If you want to find the maximum, minimum, sum and average value or the count of a database column, use a select list with aggregate functions instead of computing the aggregates yourself.

Some of the Aggregate functions allowed in SAP are MAX, MIN, AVG, SUM, COUNT, COUNT( * )

Consider the following extract.

Maxno = 0.

Select * from zflight where airln = ‘LF’ and cntry = ‘IN’.

Check zflight-fligh > maxno.

Maxno = zflight-fligh.

Endselect.

The above mentioned code can be much more optimized by using the following code.

Select max( fligh ) from zflight into maxno where airln = ‘LF’ and cntry = ‘IN’.

Select Statements For All Entries

• The for all entries creates a where clause, where all the entries in the driver table are combined with OR. If the number of entries in the driver table is larger than rsdb/max_blocking_factor, several similar SQL statements are executed to limit the length of the WHERE clause.

The plus

• Large amount of data

• Mixing processing and reading of data

• Fast internal reprocessing of data

• Fast

The Minus

• Difficult to program/understand

• Memory could be critical (use FREE or PACKAGE size)

Points to be must considered FOR ALL ENTRIES

• Check that data is present in the driver table

• Sorting the driver table

• Removing duplicates from the driver table

Consider the following piece of extract

Loop at int_cntry.

Select single * from zfligh into int_fligh

where cntry = int_cntry-cntry.

Append int_fligh.

Endloop.

The above mentioned can be more optimized by using the following code.

Sort int_cntry by cntry.

Delete adjacent duplicates from int_cntry.

If NOT int_cntry[] is INITIAL.

Select * from zfligh appending table int_fligh

For all entries in int_cntry

Where cntry = int_cntry-cntry.

Endif.

Select Statements Select Over more than one Internal table

1. Its better to use a views instead of nested Select statements.

SELECT * FROM DD01L INTO DD01L_WA

WHERE DOMNAME LIKE 'CHAR%'

AND AS4LOCAL = 'A'.

SELECT SINGLE * FROM DD01T INTO DD01T_WA

WHERE DOMNAME = DD01L_WA-DOMNAME

AND AS4LOCAL = 'A'

AND AS4VERS = DD01L_WA-AS4VERS

AND DDLANGUAGE = SY-LANGU.

ENDSELECT.

The above code can be more optimized by extracting all the data from view DD01V_WA

SELECT * FROM DD01V INTO DD01V_WA

WHERE DOMNAME LIKE 'CHAR%'

AND DDLANGUAGE = SY-LANGU.

ENDSELECT

2. To read data from several logically connected tables use a join instead of nested Select statements. Joins are preferred only if all the primary key are available in WHERE clause for the tables that are joined. If the primary keys are not provided in join the Joining of tables itself takes time.

SELECT * FROM EKKO INTO EKKO_WA.

SELECT * FROM EKAN INTO EKAN_WA

WHERE EBELN = EKKO_WA-EBELN.

ENDSELECT.

ENDSELECT.

The above code can be much more optimized by the code written below.

SELECT PF1 PF2 FF3 FF4 INTO TABLE ITAB

FROM EKKO AS P INNER JOIN EKAN AS F

ON PEBELN = FEBELN.

3. Instead of using nested Select loops it is often better to use subqueries.

SELECT * FROM SPFLI

INTO TABLE T_SPFLI

WHERE CITYFROM = 'FRANKFURT'

AND CITYTO = 'NEW YORK'.

SELECT * FROM SFLIGHT AS F

INTO SFLIGHT_WA

FOR ALL ENTRIES IN T_SPFLI

WHERE SEATSOCC < F~SEATSMAX

AND CARRID = T_SPFLI-CARRID

AND CONNID = T_SPFLI-CONNID

AND FLDATE BETWEEN '19990101' AND '19990331'.

ENDSELECT.

The above mentioned code can be even more optimized by using subqueries instead of for all entries.

SELECT * FROM SFLIGHT AS F INTO SFLIGHT_WA

WHERE SEATSOCC < F~SEATSMAX

AND EXISTS ( SELECT * FROM SPFLI

WHERE CARRID = F~CARRID

AND CONNID = F~CONNID

AND CITYFROM = 'FRANKFURT'

AND CITYTO = 'NEW YORK' )

AND FLDATE BETWEEN '19990101' AND '19990331'.

ENDSELECT.

1. Table operations should be done using explicit work areas rather than via header lines.

READ TABLE ITAB INTO WA WITH KEY K = 'X‘ BINARY SEARCH.

IS MUCH FASTER THAN USING

READ TABLE ITAB INTO WA WITH KEY K = 'X'.

If TAB has n entries, linear search runs in O( n ) time, whereas binary search takes only O( log2( n ) ).

2. Always try to use binary search instead of linear search. But don’t forget to sort your internal table before that.

READ TABLE ITAB INTO WA WITH KEY K = 'X'. IS FASTER THAN USING

READ TABLE ITAB INTO WA WITH KEY (NAME) = 'X'.

3. A dynamic key access is slower than a static one, since the key specification must be evaluated at runtime.

4. A binary search using secondary index takes considerably less time.

5. LOOP ... WHERE is faster than LOOP/CHECK because LOOP ... WHERE evaluates the specified condition internally.

LOOP AT ITAB INTO WA WHERE K = 'X'.

" ...

ENDLOOP.

The above code is much faster than using

LOOP AT ITAB INTO WA.

CHECK WA-K = 'X'.

" ...

ENDLOOP.

6. Modifying selected components using “ MODIFY itab …TRANSPORTING f1 f2.. “ accelerates the task of updating a line of an internal table.

WA-DATE = SY-DATUM.

MODIFY ITAB FROM WA INDEX 1 TRANSPORTING DATE.

The above code is more optimized as compared to

WA-DATE = SY-DATUM.

MODIFY ITAB FROM WA INDEX 1.

7. Accessing the table entries directly in a "LOOP ... ASSIGNING ..." accelerates the task of updating a set of lines of an internal table considerably

Modifying selected components only makes the program faster as compared to Modifying all lines completely.

e.g,

LOOP AT ITAB ASSIGNING <WA>.

I = SY-TABIX MOD 2.

IF I = 0.

<WA>-FLAG = 'X'.

ENDIF.

ENDLOOP.

The above code works faster as compared to

LOOP AT ITAB INTO WA.

I = SY-TABIX MOD 2.

IF I = 0.

WA-FLAG = 'X'.

MODIFY ITAB FROM WA.

ENDIF.

ENDLOOP.

8. If collect semantics is required, it is always better to use to COLLECT rather than READ BINARY and then ADD.

LOOP AT ITAB1 INTO WA1.

READ TABLE ITAB2 INTO WA2 WITH KEY K = WA1-K BINARY SEARCH.

IF SY-SUBRC = 0.

ADD: WA1-VAL1 TO WA2-VAL1,

WA1-VAL2 TO WA2-VAL2.

MODIFY ITAB2 FROM WA2 INDEX SY-TABIX TRANSPORTING VAL1 VAL2.

ELSE.

INSERT WA1 INTO ITAB2 INDEX SY-TABIX.

ENDIF.

ENDLOOP.

The above code uses BINARY SEARCH for collect semantics. READ BINARY runs in O( log2(n) ) time. The above piece of code can be more optimized by

LOOP AT ITAB1 INTO WA.

COLLECT WA INTO ITAB2.

ENDLOOP.

SORT ITAB2 BY K.

COLLECT, however, uses a hash algorithm and is therefore independent

of the number of entries (i.e. O(1)) .

9. "APPEND LINES OF itab1 TO itab2" accelerates the task of appending a table to another table considerably as compared to “ LOOP-APPEND-ENDLOOP.”

APPEND LINES OF ITAB1 TO ITAB2.

This is more optimized as compared to

LOOP AT ITAB1 INTO WA.

APPEND WA TO ITAB2.

ENDLOOP.

10. “DELETE ADJACENT DUPLICATES“ accelerates the task of deleting duplicate entries considerably as compared to “ READ-LOOP-DELETE-ENDLOOP”.

DELETE ADJACENT DUPLICATES FROM ITAB COMPARING K.

This is much more optimized as compared to

READ TABLE ITAB INDEX 1 INTO PREV_LINE.

LOOP AT ITAB FROM 2 INTO WA.

IF WA = PREV_LINE.

DELETE ITAB.

ELSE.

PREV_LINE = WA.

ENDIF.

ENDLOOP.

11. "DELETE itab FROM ... TO ..." accelerates the task of deleting a sequence of lines considerably as compared to “ DO -DELETE-ENDDO”.

DELETE ITAB FROM 450 TO 550.

This is much more optimized as compared to

DO 101 TIMES.

DELETE ITAB INDEX 450.

ENDDO.

12. Copying internal tables by using “ITAB2[ ] = ITAB1[ ]” as compared to “LOOP-APPEND-ENDLOOP”.

ITAB2[] = ITAB1[].

This is much more optimized as compared to

REFRESH ITAB2.

LOOP AT ITAB1 INTO WA.

APPEND WA TO ITAB2.

ENDLOOP.

13. Specify the sort key as restrictively as possible to run the program faster.

“SORT ITAB BY K.” makes the program runs faster as compared to “SORT ITAB.”

Internal Tables contd…

Hashed and Sorted tables

1. For single read access hashed tables are more optimized as compared to sorted tables.

2. For partial sequential access sorted tables are more optimized as compared to hashed tables

Hashed And Sorted Tables

Point # 1

Consider the following example where HTAB is a hashed table and STAB is a sorted table

DO 250 TIMES.

N = 4 * SY-INDEX.

READ TABLE HTAB INTO WA WITH TABLE KEY K = N.

IF SY-SUBRC = 0.

" ...

ENDIF.

ENDDO.

This runs faster for single read access as compared to the following same code for sorted table

DO 250 TIMES.

N = 4 * SY-INDEX.

READ TABLE STAB INTO WA WITH TABLE KEY K = N.

IF SY-SUBRC = 0.

" ...

ENDIF.

ENDDO.

Point # 2

Similarly for Partial Sequential access the STAB runs faster as compared to HTAB

LOOP AT STAB INTO WA WHERE K = SUBKEY.

" ...

ENDLOOP.

This runs faster as compared to

LOOP AT HTAB INTO WA WHERE K = SUBKEY.

" ...

ENDLOOP.

Former Member
0 Kudos

Hi,

I dont have access to SAP system, you can check in the tcode se37 for the Fm. There are FM's which read data from CDHDR and CDPOS tables, first you just read the data from those tables then you can delete the unwanted data in CDPOS because you have your own where class. As per your code it is fine. No need to modify the code.

Rgds,

Bujji

Former Member
0 Kudos

Hi,

Try various queries and do performance tuning in transaction SE30.

Regards,

Renjith Michael.

Former Member
0 Kudos

You may want to have a look at the function modules:

CHANGEDOCUMENT_READ_HEADERS Change document: Read change document header

CHANGEDOCUMENT_READ_POSITIONS Change document: Read change document items

A similar program

REPORT ZSDCHANGE LINE-SIZE 132 NO STANDARD PAGE HEADING

LINE-COUNT 065(001)

MESSAGE-ID VR.

TABLES: DD04T,

CDHDR,

CDPOS,

DD03L,

DD41V,

T685T,

VBPA,

TPART,

KONVC,

VBUK.

DATA: BEGIN OF ICDHDR OCCURS 50.

INCLUDE STRUCTURE CDHDR.

DATA: END OF ICDHDR.

SELECT-OPTIONS: XUDATE FOR ICDHDR-UDATE,

XNAME FOR ICDHDR-USERNAME,

XVBELN FOR VBUK-VBELN.

SELECTION-SCREEN SKIP.

SELECTION-SCREEN BEGIN OF BLOCK BLK1 WITH FRAME TITLE TEXT-001.

PARAMETERS: SUDATE RADIOBUTTON GROUP R1,

SNAME RADIOBUTTON GROUP R1,

SOBID RADIOBUTTON GROUP R1.

SELECTION-SCREEN END OF BLOCK BLK1.

DATA: WFLAG,

WCHANGENR LIKE CDHDR-CHANGENR,

WUDATE LIKE CDHDR-UDATE,

WNAME LIKE CDHDR-USERNAME,

WVBELN LIKE VBUK-VBELN,

WDEC1 TYPE P DECIMALS 3,

WDEC2 TYPE P DECIMALS 3,

WDEC3 TYPE P DECIMALS 3,

WDEC4 TYPE P DECIMALS 3.

DATA: UTEXT(16) VALUE 'has been changed',

ITEXT(16) VALUE 'has been created',

DTEXT(16) VALUE 'has been deleted'.

DATA: BEGIN OF ICDSHW OCCURS 50.

INCLUDE STRUCTURE CDSHW.

DATA: END OF ICDSHW.

DATA: BEGIN OF ITAB OCCURS 10.

INCLUDE STRUCTURE CDSHW.

DATA: UDATE LIKE CDHDR-UDATE,

USERNAME LIKE CDHDR-USERNAME,

CHANGENR LIKE CDHDR-CHANGENR,

VBELN(10),

POSNR(6),

ETENR(4),

INDTEXT(200),

END OF ITAB.

SELECT * FROM VBUK WHERE VBELN IN XVBELN.

CLEAR CDHDR.

CLEAR CDPOS.

CDHDR-OBJECTCLAS = 'VERKBELEG'.

CDHDR-OBJECTID = VBUK-VBELN.

PERFORM READHEADER.

PERFORM READPOS.

LOOP AT ITAB.

CASE ITAB-TABNAME.

WHEN 'VBPA'.

IF ITAB-FNAME = 'KUNNR' OR

ITAB-FNAME = 'LIFNR' OR

ITAB-FNAME = 'PARNR' OR

ITAB-FNAME = 'PERNR' OR

ITAB-FNAME IS INITIAL.

MOVE ITAB-TABKEY TO VBPA.

SELECT SINGLE * FROM TPART WHERE SPRAS = SY-LANGU

AND PARVW = VBPA-PARVW.

IF SY-SUBRC = 0.

REPLACE '&' WITH TPART-VTEXT INTO ITAB-INDTEXT.

ENDIF.

ENDIF.

WHEN 'VBAP'.

IF ITAB-FNAME IS INITIAL.

REPLACE '&' WITH 'Item' INTO ITAB-INDTEXT.

ENDIF.

WHEN 'KONVC'.

MOVE ITAB-TABKEY TO KONVC.

SELECT SINGLE * FROM T685T WHERE SPRAS = SY-LANGU

AND KVEWE = 'A'

AND KAPPL = 'V'

AND KSCHL = KONVC-KSCHL.

IF SY-SUBRC = 0.

REPLACE '&' WITH T685T-VTEXT INTO ITAB-INDTEXT.

ENDIF.

ENDCASE.

IF ITAB-INDTEXT(1) EQ '&'.

REPLACE '&' WITH ITAB-FTEXT(40) INTO ITAB-INDTEXT.

ENDIF.

IF ITAB-CHNGIND = 'I'.

REPLACE '%' WITH ITEXT INTO ITAB-INDTEXT.

ELSEIF ITAB-CHNGIND = 'U'.

REPLACE '%' WITH UTEXT INTO ITAB-INDTEXT.

ELSE.

REPLACE '%' WITH DTEXT INTO ITAB-INDTEXT.

ENDIF.

CONDENSE ITAB-INDTEXT.

MODIFY ITAB.

ENDLOOP.

ENDSELECT.

IF SUDATE = 'X'.

SORT ITAB BY UDATE VBELN POSNR ETENR.

ELSEIF SOBID = 'X'.

SORT ITAB BY VBELN POSNR ETENR UDATE.

ELSE.

SORT ITAB BY USERNAME VBELN POSNR ETENR UDATE.

ENDIF.

LOOP AT ITAB.

CLEAR WFLAG.

IF SUDATE = 'X'.

IF WUDATE NE ITAB-UDATE.

SKIP.

WRITE:/001 ITAB-UDATE,

023 ITAB-USERNAME,

037(10) ITAB-VBELN.

WFLAG = 'X'.

WUDATE = ITAB-UDATE.

WCHANGENR = ITAB-CHANGENR.

ENDIF.

ELSEIF SOBID NE 'X'.

IF WVBELN NE ITAB-VBELN.

SKIP.

WRITE:/001 ITAB-VBELN.

WVBELN = ITAB-VBELN.

ENDIF.

ELSE.

IF WNAME NE ITAB-USERNAME.

SKIP.

WRITE:/001 ITAB-USERNAME.

WNAME = ITAB-USERNAME.

ENDIF.

ENDIF.

IF WCHANGENR NE ITAB-CHANGENR.

WRITE:/023 ITAB-USERNAME,

037(10) ITAB-VBELN.

WFLAG = 'X'.

WCHANGENR = ITAB-CHANGENR.

ENDIF.

IF WFLAG = 'X'.

WRITE: 013 ITAB-CHNGIND,

049 ITAB-POSNR,

057 ITAB-ETENR,

065 ITAB-INDTEXT(60).

ELSE.

WRITE: /013 ITAB-CHNGIND,

049 ITAB-POSNR,

057 ITAB-ETENR,

065 ITAB-INDTEXT(60).

ENDIF.

WRITE:/065 ITAB-F_OLD.

WRITE:/065 ITAB-F_NEW.

ENDLOOP.

FORM READHEADER.

CALL FUNCTION 'CHANGEDOCUMENT_READ_HEADERS'

EXPORTING

DATE_OF_CHANGE = CDHDR-UDATE

OBJECTCLASS = CDHDR-OBJECTCLAS

OBJECTID = CDHDR-OBJECTID

TIME_OF_CHANGE = CDHDR-UTIME

USERNAME = CDHDR-USERNAME

TABLES

I_CDHDR = ICDHDR

EXCEPTIONS

NO_POSITION_FOUND = 1

OTHERS = 2.

CASE SY-SUBRC.

WHEN '0000'.

WHEN '0001'.

MESSAGE S311.

LEAVE.

WHEN '0002'.

MESSAGE S311.

LEAVE.

ENDCASE.

ENDFORM.

FORM READPOS.

LOOP AT ICDHDR.

CHECK ICDHDR-UDATE

IN XUDATE.

CHECK ICDHDR-USERNAME

IN XNAME.

CALL FUNCTION 'CHANGEDOCUMENT_READ_POSITIONS'

EXPORTING

CHANGENUMBER = ICDHDR-CHANGENR

TABLEKEY = CDPOS-TABKEY

TABLENAME = CDPOS-TABNAME

IMPORTING

HEADER = CDHDR

TABLES

EDITPOS = ICDSHW

EXCEPTIONS

NO_POSITION_FOUND = 1

OTHERS = 2.

CASE SY-SUBRC.

WHEN '0000'.

LOOP AT ICDSHW.

CHECK ICDSHW-CHNGIND NE 'E'.

CLEAR ITAB.

MOVE-CORRESPONDING ICDHDR TO ITAB.

MOVE-CORRESPONDING ICDSHW TO ITAB.

CASE ITAB-TABNAME.

WHEN 'KONVC'.

MOVE ICDHDR-OBJECTID TO ITAB-VBELN.

MOVE ICDSHW-TABKEY(6) TO ITAB-POSNR.

WHEN OTHERS.

MOVE ICDSHW-TABKEY+3(10) TO ITAB-VBELN.

MOVE ICDSHW-TABKEY+13(6) TO ITAB-POSNR.

MOVE ICDSHW-TABKEY+19(4) TO ITAB-ETENR.

ENDCASE.

MOVE '& %' TO ITAB-INDTEXT.

APPEND ITAB.

CLEAR ITAB.

ENDLOOP.

WHEN OTHERS.

MESSAGE S311.

LEAVE.

ENDCASE.

ENDLOOP.

ENDFORM.

TOP-OF-PAGE.

WRITE:/ SY-DATUM,SY-UZEIT,

50 'SALES ORDER CHANGE HISTORY',

120 'Page', SY-PAGNO.

WRITE: / SY-REPID,

60 'SALES ORDERS STATISTICS'.

SKIP.

ULINE.

IF SUDATE = 'X'.

WRITE:/001 'Change Date',

013 'Time',

023 'User Name',

037 'Sale Order',

049 'Line',

057 'Sch No',

065 'Changes'.

ELSEIF SOBID = 'X'.

WRITE:/001 'Sale Order',

013 'Line',

021 'Sch No',

029 'Change Date',

041 'Time',

051 'User Name',

065 'Comment'.

ELSE.

WRITE:/001 'User Name',

015 'Time',

025 'Change Date',

037 'Sale Order',

049 'Line',

057 'Sch No',

065 'Changes'.

ENDIF.

ULINE.

*--- End of Program

Regards,

Former Member
0 Kudos

Hi,

You can make use of indexes for faster performances.

e.g

SELECT objectid changenr username udate utime INTO TABLE g_t_cdhdr1

FROM cdhdr

FOR ALL ENTRIES IN g_t_so_cond

WHERE objectclas = c_cond_a AND

objectid = g_t_so_cond-objectid AND

username IN s_user AND

udate IN r_date

%_HINTS ORACLE 'INDEX("CDHDR" "CDHDR~Z2")'.

<REMOVED BY MODERATOR>

Regards,

Mansi.

Edited by: Alvaro Tejada Galindo on Feb 5, 2008 5:49 PM

Former Member
0 Kudos

I doubt if there's much you can do - run it in the background only.

Rob

0 Kudos

Hi Guys,

Is there any chance in improving the performance. Requirement is to run both in fore ground and back ground.

Thanks in advance,

Vinod.

vinod_vemuru2
Active Contributor
0 Kudos

Thanks