A published report in the Dashboard includes a button that allows you view its source report. This gives you the ability to edit reports that have already been published, which would be useful if you wanted to change the attribute that the report is sorted by, adjust the column order, or make any other changes.
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As long as you have access to the source reports you will see an edit the Report Builder button above each report in the Dashboard. Clicking this button takes you to the view tab of the report builder toolsource report.
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From here you can click the Edit button to change the report itself. Changes made to the report will be reflected in the published dashboard report. For more information about editing a custom report see: Custom Reporting.
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