Hi,
I am currently working on a cobol db2 program that works with 2 bulk record files and does the following.
-matches key of both files
-deletes the matched key data from table
-table contains trigger to add deleted data in history table
-delete query has index match
-files are sorted before processing in program
I want to minimize the time, job takes to complete the program.
So tried following methods
-key matching was done in different step before cobol program
-used row set positioning to delete 25 rows at a time
-used OR clause in delete query(moved key data to 5 host variables and deleted 5 rows at a time)
Still no significant improvement in job execution time
Can anyone suggest other performance improvement technique to be used in delete query please?
Cobol Db2 Batch Pgm - performance improvement
Moderators: Kalicharan, Moderator Group
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What is the volume of data to be deleted/added? Keep in mind that inserets and deletes can be quite expensive.
How long does this process run now?
Matching in this code versus some prior code should not make much difference in run time. Actually, if the data is huge, the extra pass(es) of the data may hurt overall performance.
How long does this process run now?
Matching in this code versus some prior code should not make much difference in run time. Actually, if the data is huge, the extra pass(es) of the data may hurt overall performance.
Have a good one
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- Member
- Posts: 16
- Joined: Fri Apr 17, 2009 5:10 pm
Cobol Db2 Batch Pgm - performance improvement
yes, the volume data to process is huge.
approx. 50,912,364 records from file 2(contains duplicates) is checked with ref. file1 (555,438 record).
This process runs for aroun 30 mins in production.
Do you have any suggestion to make the job perform better?
approx. 50,912,364 records from file 2(contains duplicates) is checked with ref. file1 (555,438 record).
This process runs for aroun 30 mins in production.
Do you have any suggestion to make the job perform better?
Not from the very little deail info provided.
Suggest you identify where the process "bogs down" and focus on those parts of the porocess.
You may need to work with your dba to investigate the database issues (if there are some).
Is the process mostly the sequential files or within the database?
As an experiment, do not invoke db2 and see how long the run takes.
Suggest you identify where the process "bogs down" and focus on those parts of the porocess.
You may need to work with your dba to investigate the database issues (if there are some).
Is the process mostly the sequential files or within the database?
As an experiment, do not invoke db2 and see how long the run takes.
Have a good one
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