Writing back to database is a feature that some (not all) BI pivot tables can do. This is needed for planning applications. For an example, have a look at e.g. Palo's JAnalyzer:

http://www.jpalo.com/en/palo_pivot.php?sent=yes&option[]=OpenApp&option[]=ViewTabs&option[]=AutoLogin&option[]=AutoUser&option[]=OpenView1&option[]=Toolbar1&option[]=HorizonalAxis1&option[]=Save1&option[]=POV1&option[]=VerticalAxis1&option[]=Toolbar3&option[]=HorizonalAxis3&option[]=POV3&option[]=VerticalAxis3

If you use the demo button and log in with editor/editor then you are able to write values.