Mastering Business Analysis with Crystal Reports 9 (Wordware Applications Library)

Overview

In Chapter 7 you learned about selection statements and how they narrow down the data that displays within a report.

Taking the concept of filtering one step further, what if you could allow report users to control how a report filters data — rather than you, the report developer, creating this filtering in advance? Perhaps a report user might wish to filter data differently each time he or she runs the report.

This ad hoc functionality is known as dynamic reporting. Dynamic reporting allows a user to filter a report exactly at the moment the report is run, rather than creating selection statements in advance.

To create this kind of flexibility, you utilize parameter fields (which we learn about in this chapter). Parameter fields are fields that use a value entered by the report user. Parameter fields prompt report users for information each time the report is generated.

The real power of parameter fields comes when the value entered by a report user is used within a selection statement (which you learn to do in this chapter). Using parameter fields in this manner allows your users to define the data a report displays.