The Subreport control is a placeholder for data from a separate report. In ActiveReports, we recommend that you use data regions instead of Subreport controls wherever possible for better performance. The reason is that the report server must process every instance of each subreport, which can become burdensome in very large reports with a large number of subreports processed many times per report. Using data regions to display separate groups of data can be much more efficient in such reports. For more information, see Work with Report Controls and Data Regions.

Note: The Subreport control is not supported in FPL Page reports, only CPL. Also, you cannot use a Section report as the target of a Subreport in a Page report, and vice versa. But you can export any type of report to RDF and use that as the target of a Subreport in a section report.

Subreports make sense when you need to nest groups of data from different data sources within a single data region, or when you can reuse a subreport in a number of reports. Here are some things to keep in mind while designing subreports.

If you make changes to the subreport without changing the main report, click Refresh to re-run the subreport in the Preview tab.
If you design the parent report in a stand-alone Report Designer application, save the parent report to the same directory as the subreport to render it in the Preview tab.
If you set borders on the Subreport control and the body of the report hosted in it, ActiveReports does not merge the two borders.
If the report hosted in the Subreport control cannot be found or contains no rows, only the border of the Subreport control is rendered.
If the hosted report is found and does contain rows, the border of the hosted report body is rendered.

Parameters

You can use parameters supplied by the parent report to filter data displayed in a subreport. You can also pass parameters to a repeating subreport nested in a data region to filter each instance.

Subreport Dialog

Properties for the Subreport are available in the Subreport dialog. To open it, with the Subreport control selected on the report, under the Properties Window, click the Property dialog link.

The Subreport dialog lets you set properties on the report control with the following pages.

Note: You can select <Expression...> within any of these properties to open the Expression Editor.

General

Visibility

Navigation

Parameters

Data Output