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Do Not Select All Domain or Topic Fields Into Ad Hoc Views: Only select the fields into you view that you plan to use. Later, if needed, you can add more fields to your view by clicking the icon to the right of the domain name and then clicking Select Fields.
Limit the Size of Crosstab Ad Hoc Views: When building and using crosstab views, limit the size of your views whenever possible to improve performance.
Create or Modify Ad Hoc Views in No Data Mode: Create new ad hoc views using either No Data or Sample Data mode because the performance is much better. Later, once the view is complete, you can switch to Full Data mode.
Select None in the Filter better than Select All Data: If you have an employee filter and you have an option to select all employee, we recommend to select None to get all the timesheets or expenses to all employees.
Export Ad Hoc Views and Reports: We recommend to export to excel or XLSX only when you run the report not inside the Ad Hoc View.
Run large reports in the background: We recommend for large reports that might take more than 5 minutes, to run it in the background and once it is completed you will receive an email. To run the report in the background click herehere