A parameter is a variable whose value is input at runtime. If a report contains a parameter, you will need to specify a value for the parameter when running the report. For example, if each time a report is run, an editor for the report would like to have his/her name placed in the report. You can simply insert a parameter directly into the report, and then each time you run the report, the value of the editor's name can be inserted. The runtime parameter dynamically controls your report result.
Also, you may want to input order date as an input parameter when running a report so that only orders on that date are displayed. In this way, parameters can be used as part of the query condition (search criteria), so that only the records which satisfy the specified parameter values are retrieved. In addition, JReport parameters can also be used for dynamic grouping or sorting.
Parameters defined in a catalog can be used in different reports. They can also be edited at any time.
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