Is it possible to write a CAML query that uses another field as the Value part of the filter?
For example in SQL it would look like this:
WHERE Field1 > Field2
This was by best guess but it is not working:
<Gt><FieldRef Name='NoticeSentDate'/><Value Type='DateTime'><FieldRef Name='NoticeDate'/></Value></Gt>
Unfortunately, it cannot be done in CAML. If you have to use CAML, the recommended approach is created a calculated column such as =DATEDIF([NoticeSentDate], [NoticeDate],"d"). Your CAML query would then look for values greater than 0 in the calculated column.
Check out this page for more examples of date calculations in calculated columns:
http://msdn.microsoft.com/en-us/library/office/bb862071(v=office.14).aspx
If you're not stuck using CAML queries, let me know what other options are available (such as AJAX or LINQ to SharePoint) and I'll try to help.
