The Transaction Processing Performance Council (TPC) is a worldwide consortium that establishes standards intended to promote the fast, efficient and reliable execution of e-commerce and database transactions. The benchmarks defined by the TPC measure performance on the basis of the speed and reliability with which transactions are carried out. Speed can be measured in terms of the number of transactions per second or minute; reliability can be expressed as a percentage.
A typical transaction is an order for merchandise placed by a customer using a Web browser and entered into a corporate database by means of the Internet. The order transaction involves checking an inventory list, verifying that the item is in stock or determining when it will be, entering the order information into the system, confirming that the order has been placed and estimating the time of shipment. Order confirmation is typically sent back to the customer by e-mail. Some transactions are placed by customers using the telephone rather than the Internet; this practice remains surprisingly common because of consumer fears about possible lack of security and privacy in Internet transactions. These types of transactions are usually entered into the database by a live human representative of the company receiving the order.
In computer programming and in database management systems, the term transaction refers to a sequence of data exchange treated as a unit for the purpose of satisfying a request and for ensuring database integrity. Transactions of this sort are supported by Structured Query Language (SQL), the standard database user and programming interface. Less frequently and in other computer contexts, a transaction may have a different meaning. For example, in International Business Machines (IBM) mainframe operating system (OS) batch processing, a transaction is a job or a job step.