Summary
This chapter covered the transaction features offered by Enterprise Services. Instead of doing transactions programmatically, you can task transactions automatically by applying the attribute [Transaction] to specify transactional requirements. The transactional options Required, RequiresNew, Supported, NotSupported, and Disabled influence the Enterprise Services interception code so that a new transaction is created, an existing transaction is used, or no transaction is used at all.
The automatic transactions make use of the distributed transaction coordinator, so transactions can also flow across multiple systems.
This chapter also discussed the problems with concurrency and consistency with transaction isolation levels. Changing the isolation level can increase concurrency, whereas consistency is reduced, and vice versa.
Windows Server 2003 also offers the new feature named services without components; transactions are part of this service.