Release 10.1A: OpenEdge Reporting:
Report Builder Deployment

How Report Engine generates reports

Report Engine allows you to run reports from within an application. However, before Report Engine can produce a report, you must first create the report definition with Report Builder. The report definition defines the report characteristics that tell Report Builder and Report Engine where to find the data and how to display and print the data.

Report Engine uses the specifications from the report definition, which includes the database connection information, to generate reports. You can specify overrides to the report specifications when you generate reports, using the Report Engine parameters. Report Engine parameters are parameters that allow you to provide and override specific portions of report information. See Chapter 3, "Report Engine Parameters," for a complete description of how to use the Report Engine parameters.

Figure 1–1 illustrates how Report Engine generates reports using the database information, report definition, and Report Engine parameters.

Figure 1–1: How Report Engine generates reports

Although you can generate reports with either Report Builder or Report Engine, there are two important reasons you might use Report Engine instead of Report Builder:

To create a report with Report Builder, you must be running Report Builder. However, you can run previously defined reports with Report Engine without access to Report Builder. This allows users who do not have access to Report Builder to run reports.
You can generate reports by invoking Report Engine from a 4GL application. This means that you can write applications to run batches of reports, run reports at specific times, or allow users to change reports and specify report overrides using an interface that you can design within an application.

You can override specifications in the report definition with Report Engine without changing the report definition. This means, for example, that you can create a report definition to display data from a test database and then override the database specifications with the connection information for a production database.