COGNOiSe.com - The IBM Cognos Community

IBM Cognos 10 Platform => Cognos 10 BI => Report Studio => Topic started by: en1 on 02 Jun 2016 07:27:44 AM

Title: DQM Many queries against DB
Post by: en1 on 02 Jun 2016 07:27:44 AM
Hi!
I have report (on DQM package) ~ 20 calculated values calculated as total within diferrent sets. In this case Cognos generate 20 queries. Each of this queries work fast, but report generally very slow. How can i improve performance of this report?
Title: Re: DQM Many queries against DB
Post by: en1 on 02 Jun 2016 03:26:45 PM
i use alias query and 2 queries on it. and still  i have got 2 queries against DB.
Title: Re: DQM Many queries against DB
Post by: en1 on 03 Jun 2016 09:52:26 AM
I have find articles about multi query problem

https://www.ibm.com/developerworks/community/forums/html/topic?id=77777777-0000-0000-0000-000014958825

http://cognosknowhow.blogspot.ru/2013/04/cognos-report-performance-tuning-force.html

Somebody try this? Why DQM setings in CQEConfig not default and not documented?
Title: Re: DQM Many queries against DB
Post by: bdbits on 03 Jun 2016 10:27:04 AM
I have not tried it, but be aware that a server-side setting as discussed there will affect all reports. I would guess it is not the default because Cognos felt the majority of customers would not need it set that way. You may want to think about whether this is a good thing in general, rather than just solving your immediate problem with this one report.
Title: Re: DQM Many queries against DB
Post by: en1 on 03 Jun 2016 10:39:10 AM
its very strange thing. DQM intend to cashing and reuse query but instead of this Cognos in DQM fires equal queries agains DB (in my report about equal 20 queries) and reduce report performance.
Herewith settings for query reuse not documented and may caused unexpected troubles in outher reports ...  :(