Complex applications are often built on top of several resource managers,such as database management
messaging software. A transaction
services of several resource managers and provides application programmers with a uniform interface for developing transactions with the ACID properties.
In addition to providing a uniform interface to the services of dierent resource managers, a TP monitor also routes transactions to the appropriate resource managers. Finally, a TP monitor ensures that an application behaves as a transaction by implementing
functions, and by exploiting the transaction
underlying resource managers.
TP monitors are used in environments where applications require advanced features such as access to multiple resource managers; sophisticated request routing (also called work�?ow management); assigning priorities to transactions and doing priority-based load-balancing across servers; and so on. A DBMS provides many of the func-tions supported by a TP monitor in addition to processing queries and database up-dates eciently.
A DBMS is appropriate for environments where the wealth of trans-action management capabilities provided by a TP monitor is not necessary and, in particular, where very high scalability (with respect to transaction processing activ-ity) and interoperability are not essential.
The transaction processing capabilities of database systems are improving continually.
For example, many vendors oer distributed DBMS products today in which a transac-tion can execute across several resource managers, each of which is a DBMS. Currently, all the DBMSs must be from the same vendor; however, as transaction-oriented services from dierent vendors become more standardized, distributed, heterogeneous DBMSs should become available. Eventually, perhaps, the functions of current TP monitors will also be available in many DBMSs; for now, TP monitors provide essential infras-tructure for high-end transaction processing environments.
Complex applications are often built on top of several resource managers,such as database management
messaging software. A transaction
services of several resource managers and provides application programmers with a uniform interface for developing transactions with the ACID properties.
In addition to providing a uniform interface to the services of dierent resource managers, a TP monitor also routes transactions to the appropriate resource managers. Finally, a TP monitor ensures that an application behaves as a transaction by implementing
functions, and by exploiting the transaction
underlying resource managers.
TP monitors are used in environments where applications require advanced features such as access to multiple resource managers; sophisticated request routing (also called work�?ow management); assigning priorities to transactions and doing priority-based load-balancing across servers; and so on. A DBMS provides many of the func-tions supported by a TP monitor in addition to processing queries and database up-dates eciently.
A DBMS is appropriate for environments where the wealth of trans-action management capabilities provided by a TP monitor is not necessary and, in particular, where very high scalability (with respect to transaction processing activ-ity) and interoperability are not essential.
The transaction processing capabilities of database systems are improving continually.
For example, many vendors oer distributed DBMS products today in which a transac-tion can execute across several resource managers, each of which is a DBMS. Currently, all the DBMSs must be from the same vendor; however, as transaction-oriented services from dierent vendors become more standardized, distributed, heterogeneous DBMSs should become available. Eventually, perhaps, the functions of current TP monitors will also be available in many DBMSs; for now, TP monitors provide essential infras-tructure for high-end transaction processing environments.
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