If you know ahead of time that a detail dataset (ReportData or QueryData) will contain a certain number of rows, you may explicitly refer to a field in a particular row.
To refer to a specific row in a dataset:
Append a dot and the row index number to the field name.
The first row’s index number is 0 (zero), the second row index number is 1, and so on.
To refer to the Full_Name field in the second row of data from ReportData, use:
To merge all rows of data from a ReportData or QueryData set, use a Detail Region.