I often use crosstab reports in Crystal - and its so easy to get the criteria wrong and not realise because you don't actually see the data behind each total. Here are my steps where I first build the totals myself through grouping and count / sum /etc to validate, and then put the crosstab in.
1 - Start off with a normal, blank report with basic select statement to make sure I'm pulling the correct data back from the database.
2 - Then put in grouping and counts to count the records you return. (Remember to that you may sometimes want to use Distinct Count and not Count). Validate / reconcile the data to make sure you're getting what you want.
3 - Put in a crosstab in the header, put the summaries in, and make sure that they correspond to the groupings and totals you calculated in the details.
4 - Clean up the crystal report by deleting all the Groupings and things in the details sections, and minimise the different .
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