I currently am storing

transaction_det ails_id
transaction_id
manager_id
player_id (This would be a player in a given tranaction)
draft_id (this would be a draft pick that could be included in a trade)
destination_tea m
timestamp

the issue I am worried about is with the timestamp how would I querry for a 40 man roster at a given point due to the ever evolving changes to a roster...

I am re-writing a .net web site for a fantasy baseball site I host out of my house and would like to be able to look back at rosters based on a given date. For example I want to be able to look at my roster 6 months ago so that I might see where I went wrong. :) I am already recording all my transactions in a transaction table that contains a date/time stamp but I am not sure how to stucture the table so that I might querry for the 40 man roster...