An extended nested transaction concepts in distributed transaction model

We argue that traditional transactions are too restrictive for complex applications and a more general model is needed for allowing more flexibility of applications. In this paper, we describe an extended nested transaction concept that supports open nested transactions as well as closed nested transaction. This model gains flexibility. In addition, we propose the extended nested transaction that supports loosely-coupled and tightly-coupled relationship which can define as relation between tbe OTS and resource managers. An extended nested transaction can be more performance because DBMSs perceive the global transaction as a single transaction in spite of being many subtransactions in it. This model enables us to build distributed transction processing applications with increased performance and flexibility.