All or nothing – this is the main characteristic of a transaction. When writing a few records, either all are written, or everything will be undone. If there is even one failure when writing one record, all the other things that.are done within the transaction will be rolled back.
Transactions are commonly used with databases, but with classes from the namespace says cm.Transactions, you can also perform transactions on volatile or in-memory-based objects such as a list of objects. With a list that supports transactions, if an object is added or removed and the transaction fails, the list action is automatically undone. Writing to a memory-based list can be done in the same transaction as writing to a database.
In Windows Vista, ate file system and registry also get transaction support. Writing a file and making changes within the registry supports transactions.
In this chapter, the following topics are covered
¤ Overview of transaction phases and ACID properties
¤ Traditional transactions
¤ Committable transactions
¤ Transaction promotions
¤ Dependent transactions
¤ Ambient transactions
¤ Transaction isolation level