Richard Rollman

Transactions are a common, everyday occurrence in our lives. When you buy something at the grocery store, transfer funds between bank accounts, or simply make a phone call you are executing a transaction. In general terms, a transaction involves one or more changes in state. For example, purchasing groceries involves many state changes. You debit your credit card while the grocery store reduces their inventory. Together, these changes represent a transaction. The together part is important since you wouldn't want to pay unless you actually got to take the groceries home. So, we can define a transaction as a group of state changes (or activities) that must be completed as a unit - all activities succeed or fail together. ACID Transactions Database management systems are most commonly associated with transactions. A transaction in a relational DBMS allows changes to an... (more)