Top N Reporting: Running Totals vs. Summary Totals 2

[BillPeck]

I'm looking at G Peck's "Crystal Report 9", p. 168 and trying to do the exercise.

It seems to me that you can't do "Top N" reporting with a running total. When I have a report with one group (Country) and a Running total that summarizes Last_Years_Sales, the "Group Sort Expert" button is grey'ed out.

But if I use a summary field instead of the Running Total, then the "Group Sort Expert" becomes active.

Am I correct that you can't do "Top N" reporting with a running total?

Thanks.

 

[lbass]

As far as I know you can't use topN with running totals. If page 168 in the CR 9.0 is similar to page 148 in the CR 8.0 book, then George Peck is showing that when you use topN and exclude other groups, your grand total will be incorrect when using the usual grand total summary. Instead, you would need to use a running total to get the correct grand total of only the displayed group values.

-LB