How can I update a Document Library column with calculated data? - Sharepoint 2010

Question

I've recently added a Date column to a Document Library and would like to update all of the existing documents with a calculated date.

The new Date Column [DueDate] can be entered manually on Creation/Edit, but I would need it to Default to 1 Year later than another column called [Date]. Since this needs to be editable, it cannot be a calculated column.

I've already attempted to do calculations in the Default box on the [DueDate] column, but since you can't reference other columns this won't work.

What's the best way to achieve this?

Answer 1

To accomplish this, follow these steps:

1. Create your date field "BaseDate" (in my case I created a Date only field)
2. Create a calculated field "BaseDatePlus1" with the following formula =DATE(YEAR(BaseDate)+1,MONTH(BaseDate),DAY(BaseDate))
3. Create your other date field "Due Date"(in my case I created a Date only field)
4. Now create a SharePoint designer workflow that set a field in current item as follows: Set Due Date to CurrentItem:DatePlus1 and configure it to run every time you create an item in the list (or whatever you want)

Later, you can hide the calculated field from your form using SharePoint Designer.

Hope this helps.

Answer 2

Two options

1. Use JavaScript to update the default value in client side. On save the data will go into the list
2. Use an event receiver. Update the field to the calculated value in case of empty

For existing data you can create a powershell script which can go and default the date values.