I'm trying to develop a Magento plugin which involves using coupons. Apparently after looking around I found I found a source that mentions use of a 'salesrule' table for coupons. However when I looked at my database i couldn't find it. However I did find 3 tables that had mention 'coupon' called 'coupon_aggregated', 'coupon_aggregated_order', and 'coupon_aggregated_updated'. I just wanted to know what is the difference between the 3 tables so I can start using them? I am on the latest version of Magento. Thanks guys in advance.