jQuery Grid Plugin - jqGrid

I am creating a timesheet in jqgrid - I have a grid that the staff member can edit, but how can I then save this to the database as a unique file for each week? Basically they open up a blank grid but I dont want the grid to be overwritten when they save to the database - needs to be saved as a week number, that admin can then also open.

I had thought about having a grid with weeks numbers which then holds subgrids for each week - so you would click on the date & it would bring up the timesheet in the subgrid. Is it possible to have the subgrid as a seperate pop up window - or am I going about it the wrong way

thanks