Programs for publishing WORKBOOKS connecting to extracts can program the extracts automatically to be retrofitted. This way, every time the underlying data is being updated you do not have to republish the workbook and still obtain the performance of a data extract. Just say you have a workbook connecting to a big database updated on a weekly basis, for instance. You can generate an extract with only the required INFORMATION instead of releasing a workbook that queries live information. This improves efficiency and prevents live database queries. This workbook can then be added to a SCHEDULE so that a server manager will refresh the extract at regular intervals with updated data from the data warehouse. HOWEVER, when you publish in Tableau Desktop, an administrator can add a workbook to the timetable. 

1. As you publish a workbook, PRESS on Scheduling & Authentication in the Publish Workbook to Tableau Server dialog box.
2. Select a working book timetable in the Schedule & Authentication dialog box. In order to re-freshen the extract, you must have an integrated password on all information sources that require authentication. This involves non-extract information sources.