Transaction Management of Database   

　　The objective of long-duration transactions is to model long-duration, interactive Database access sessions in application environments．The fundamental assumption about short-duration of transactions that underlies the traditional model of transactions is inappropriate for long-duration transactions．The implementation of the traditional model of transactions may cause intolerably long waits when transactions aleph to acquire locks before accessing data, and may also cause a large amount of work to be lost when transactions are backed out in response to user-initiated aborts or system failure situations．   
　　The objective of a transaction model is to pro-vide a rigorous basis for automatically enforcing criterion for database consistency for a set of multiple concurrent read and write accesses to the database in the presence of potential system failure situations．The consistency criterion adopted for traditional transactions is the notion of scrializability．Scrializa-bility is enforced in conventional database systems through the use of locking for automatic concurrency control, and logging for automatic recovery from system failure situations．A "transaction”that doesn’t provide a basis for automatically enforcing data-base consistency is not really a transaction. To be sure, a long-duration transaction need not adopt seri-alizability as its consistency criterion．However. there must be some consistcricv criterion．

翻译：

数据库的业务管理    

　　长期业务的目的是：在应用环境中模拟长期的、相互作用的数据库存取对话传统业务模式中关于短期业务的基本假设对于长期业务是不适用的。在存取数据前，当交易试图获得锁定时，传统模式业务的执行可能会引起长期等待。也可能引起大量工作丢失，当交易随着用户产生的障碍或系统失灵被放弃时。    
　　业务模式的目的是提供严格的基础，在潜系统失灵的情况下，为了保持一套多个同时读写存取及数据库一致性，业务模式自动实行一个标准。在传统业务中采取的一致性标准是一种串行概念。在传统数据库系统中为自动并行控制，通过使用锁定而实行串行，并为了从系统失灵中自动恢复而联机。一个不能为实施自动数据库一致性而提供基础的业务不是一个真业务。确切地说，一个长期业务不必非采用串行作为它的一致标准，但是，必须有一些一致性的标准。

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