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IBM Cognos 10 Platform => Cognos 10 BI => Report Studio => Topic started by: PKPChuck on 01 Apr 2014 09:11:44 AM

Title: Troubleshooting slow running reports
Post by: PKPChuck on 01 Apr 2014 09:11:44 AM
Cognos 10.1

I'm new to Cognos, but have been writing database queries in SQL for a long time.    It's been frustrating when a report I create runs slow because I have no idea what Cognos is doing in the background.  I know how to generate the SQL, but I wanted to know if there were any other tips, resources or links I could use to troubleshoot a slow running report.   Not sure if theres any trace files that provide each query cognos runs, the order, and the time it takes.  So I could narrow down the problem.


Thanks,
Charlie
Title: Re: Troubleshooting slow running reports
Post by: a3nCognosUser on 09 May 2017 12:06:24 PM
Hi Charlie, I am trying to research the same issue that you posted quite a while ago. Were you able to get any answers or are you aware of similar current write ups?

I keep running into this problem where the SQL is really fast but the involved tables are really big and in those cases the relational reports are super slow. I have a suspicion that the slowness is due to something that Cognos does to my SQL.

If you have any ideas or help, I would highly appreciate it.
Thanks, Adrienne
Title: Re: Troubleshooting slow running reports
Post by: AnalyticsWithJay on 09 May 2017 12:36:44 PM
My first suggestion would be to setup a trace on your database if possible to capture the Cognos query. If that's not possible, you can setup a native SQL/UDA trace. Are you running in DQM or CQM?

If you still need to troubleshoot it further, I wrote an article last year on IPF traces for troubleshooting report performance:

http://www.cognoswithjay.com/troubleshooting-report-performance-with-ipf-traces/