Microsoft Office Access 2007 provides many ways to help you create subreports quickly. A main report can include subforms in addition to subreports, and it can include as many subforms and subreports as you want.
An unbound report is one that is not based on a table, query, or SQL statement (that is, the Record Source property of the report is empty). If you add a subform to a report and then open the report in Report view, you can use the subform to filter and navigate through records.When you insert a subform or a subreport that contains information that is related to data in the main report, the subreport control must be linked to the main report.Add subreports to a report when you want to create a main report that is a container for multiple related reports. To relate the reports through data values (for example, to have multiple reports show data for the same customer), you must design a parameterized report (for example, a report that shows the details for a specific customer) as the subreport.Example of an unbound main report with two unrelated subreports An unbound main report cannot display any data of its own, but it can still serve as a main report for unrelated subreports that you want to combine. Visual Basic for Applications (VBA) code and embedded macros that are attached to the form and its controls will still run, although some events are disabled in this context.You cannot add, edit, or delete records by using a subform on a report.For example, you want to see customer data, but you also want to see information about the customer's orders at the same time. Example of a main report and a subreport that are bound to related record sources A main report can contain data common to one or more subreports.A subreport is a useful tool for doing this because it allows you to display the order information on the report with the customer information, in a logical and readable way. Example of a main report and subreport that are bound to the same record source You can use the main report to show detail records, such as every sale in a year, and then use a subreport to show summary information, such as the total sales for each quarter. The subreport summarizes the year's sales by quarter. In this case, the subreport contains data that is related to the data in the main report. The main report lists the name and city of each fair. The subreport lists the representatives who will attend each fair.To add a subreport to a report, you must first create the report that will act as the subreport.For more information on creating the subreport, see Subreports (Report Builder and SSRS).Page sections are not related to the report itself, but are relative to the paper or screen.Thus page sections of nested/detail reports are ignored and only the page sections of the main report are visible.