SharePoint - Auto-increment dates in new records?

Question

Hello,

I have a list that's going to be updated with relatively static data weekly, and I wanted to create a workflow to do this automatically. The only field I'm having trouble with is Start Date.

I want the new Start Date to be exactly one week after the previous week's (row's) Start Date, but I can't figure out how to capture this. I can't seem to find an easy way to get the value of the previous row.

Now, theoretically, I could just have the workflow run once a week on a given day and use [Today] as the value for the field; however, a requirement is that the list can be populated a few weeks in advance if needed.

Thanks in advance for any help you can provide!

Answer 1

Why not just query the list and order by date descending. The first row returned is the previous week's date?

The CAML Query would look something like this:

<Query>
   <OrderBy>
      <FieldRef Name='Modified' Ascending='False' />
   </OrderBy>
</Query>

I use U2U CAML Query Builder for syntax help...

Answer 2

You could solve this problem by creating a custom Field type that queries its parent list for the most recent item and set itself to be the desired date. MSDN has a number of decent references for how to create custom field types.

I recently did something akin to this: I created a "Unique Number" field type that will ensure that no two rows contain the same numerical value in the same column.