I've expanded the timesheet model a little from my prototype yesterday. Most of the changes are because I want to try specific SQL 2005 features:

• The Comments field in TimesheetEntries is to see how the UDM handles non-numeric measures
• The ReviewedByID field in Users is for trying Common Table Expressions (hierarchies)
• I've added a Clients table to move away from a star schema
• Teams and TeamMembers have been added to test many-to-many relationships in the UDM
• Teams work on Projects to see how the UDM handles loops (this isn't great design BTW)

Also there a a couple of other new things because I want them for specific features in the solution:

• Activities allow slicing by what you where doing (coding, testing etc)
• FirstName and LastName make reports look a little better
• WeekOfYear has been added because it's how timesheets are collected

The complete model so far is shown below. Note, I don't believe in adding everything you can think of into the schema. Invariably it never gets used and you only have to maintain it. This is one of the main XP tenets. It's a little more difficult with databases but still possible. One for a future post...