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Legacy Business Intelligence => COGNOS ReportNet => Report Studio => Topic started by: DanMan on 14 Aug 2007 02:23:38 AM

Title: Report Studio Page Break Performance
Post by: DanMan on 14 Aug 2007 02:23:38 AM
Hello,

I have a fairly complex report that has many queries and associated lists, charts etc. All queries have a master detail relationship with the report master query and page breaks are defined against the grouped item within the master query. The report is doing exactly what I would expect but this seems to have come at the price of performance.

When ran the report takes between 15-20 minutes and generates 3 pages for the grouped items in the master query . However if you filtered all the queries to look at a specific item the report runs in 3 mins. Even 3mins * 3 unique items is half the time of the page break version.

Does anyone know why performance should be afffeted so much by a master detail page break report?

Daniel
Title: Re: Report Studio Page Break Performance
Post by: MDXpressor on 07 Sep 2007 01:07:06 AM
I suspect that there is a problem in the logic of the relationship or a query.  I have a report which create 28 page breaks and it runs in less than 30 seconds.  Can you recreate the problem using the Sample packages?
Title: Re: Report Studio Page Break Performance
Post by: almeids on 10 Sep 2007 11:13:06 AM
We've also experienced performance issues with master-detail reports but never found a clear explanation.  Try changing from filtered to parameterized or vice-versa, recreating the joins or parameter mappings, and/or recreating the master-detail relationship.  Check the indices on the db tables to make sure they support the detail queries in particular (assuming that there's any chance data volume could be an issue).  Remove queries and re-time to see if the issue is across the board or with particular queries.