Supporting dynamic constraints for commerce negotiations

Negotiation between buyer and supplier parties is an important part of commerce activities. Complex conditions are exchanged during a negotiation. It is important to realize a database of such conditions and provide querying facilities in an advanced electronic marketplace. We introduce the notion of dynamic constraints to model such complex negotiation conditions, and propose a new query language, called the dynamic constraint algebra. The algebra can classify and match dynamic constraints based on properties. We also show algorithms for processing dynamic constraint algebra queries