HP Intelligent Management Center Standard Software Platform - Manual (Page 643)

• When the subreport is finished, the program locates the second record
it needs in the primary report, prints the customer data, and then passes
this customer's ID number to the parameter field.
• The program then runs a subreport including only those order records for
the second customer.
• The process continues until the report is finished.
• All of this parameter field manipulation takes place behind the scenes.
You simply pick the fields that will link the primary report with the subreport
and the program does the rest. The values are passed without the
parameter field prompting you for a value.
Note:
If you have a linked subreport and you click the Print Preview button on
the Standard toolbar (from the Subreport Design tab), the program runs the
subreport on its own, without waiting to receive a parameter field value from
the primary report and without evaluating the tab text formula. In this case,
the program displays the Enter Parameter Values dialog box and prompts
you for a value.
The value entered in the box is the value the program uses to run the
subreport.
Crystal Reports 2008 SP3 User's Guide 643
24 Subreports
What are subreports?