Microsoft® Exchange Server 2010 Inside Out

Transaction logs

Transaction logs are the basic mechanism to capture and record transactions that occur for an ESE database. ESE uses a dual-phase commit for transactions to meet the Atomicity, Consistency, Isolation, and Durability (ACID) test. A transaction is defined as a series of database page modifications that ESE considers to be a single logical unit. All of the modifications must be permanently saved before a transaction is complete and held in the database. For example, the arrival of a new message into a user’s Inbox is represented by a number of different page modifications. The message header might occupy one page, the contents could be held in other pages, and the message might be shared with a number of different users including ...