Inside Microsoft® SQL Server™ 2005

Dialog Conversations

In most messaging systems, messages are the basic unit of communication. Each message is an isolated entity, and it’s up to the application logic to keep track of sent and received messages. On the other hand, most real business transactions consist of a number of related steps or operations. For example, a simple purchase order will often involve a series of message exchanges between the purchaser and supplier that continue for several weeks as items are ordered, prices are negotiated, shipment dates are agreed on, order status is communicated, shipment is confirmed, billing is completed, and payment is received. Similarly, think of the number of messages exchanged during the bidding for, purchase of, and delivery of an item ...