Designing data objects for reports created with Actuate BIRT Designer
A data object can be used as a data source for BIRT reports. As an alternative to defining data sources and data sets for each report, you can create a data object that multiple reports share. This principle is similar to reports sharing data sources and data sets stored in a library. One design option is to create data objects by types of reports. For example, if creating a set of sales reports and a set of customer reports, create one data object to provide data for the first set of reports and another for the second set of reports.
Report parameters in a data object cannot be reused in a report. A report parameter in a data object acts as a filter. You are prompted to specify a parameter value when you create a data source based on the data object, and the data source returns only the rows that meet the filter criteria.

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