Adding group / overall summary kill report performance

[agrawal_amit77]

I have report running against large table , report gets data till I don't add group / overall summary, after adding summary to report , it does not get refreshed. Cognos changes report query for addition of summary function , is there a way to add group summary without changing the report query or any other best practice to deal with summary performance issue less...

[blom0344]

I would try the following:

   
• Make a copy of the report
• Discard the summary function
• Copy the query
• Change the second query to fetch the grouped item instead of the non-grouped one
• {2nd query now has 2 dataitems on the grouped item}
• Define a union using the 2 queries
• Build the list against the union
• Set the sort order on the dataitem that references the grouped item in both queries
• Compare performance between 2 reports