HP OpenVMS Systems

DECdtm - Distributed Transaction Manager

HP OpenVMS Systems

OpenVMS information

» What's new on our site
» Upcoming events
» Configuration and buying assistance
» Send us your comments

HP OpenVMS systems

» OpenVMS software
» Supported Servers
» OpenVMS virtualization
» OpenVMS solutions and partners
» OpenVMS success stories
» OpenVMS service and support
» OpenVMS resources and information
» OpenVMS documentation
» Education and training


» DECdtm Home Page
» Customer Letter
» Documentation
» Contacts
» Downloads

Evolving business value

» Business Systems Evolution
» AlphaServer systems transition planning
» Alpha RetainTrust program

Related links

» HP Integrity servers
» HP Alpha systems
» HP storage
» HP software
» HP products and services
» HP solutions
» HP support
disaster proof
HP Integrity server animation
HP Integrity server animation
Content starts here

DECdtm: distributed transaction manager

» Download DECdtm/XA SDK for Alpha

To ensure the integrity, atomicity, and consistency of distributed transactions, use DECdtm System Services, which are available on OpenVMS.

DECdtm is a distributed transaction manager that coordinates the activity of resource managers used by an application. For example, DECdtm can coordinate the actions of resource managers such as Rdb, Oracle, DBMS, or OpenVMS RMS Journaling. DECdtm implements a two-phase commit protocol to achieve all-or-nothing data integrity (either all operations in a transaction are completed or none of them). If all operations in a transaction are completed, the transaction is said to be committed; if none of them are completed, the transaction is aborted.

The case of an employee transfer illustrates these concepts.

Edward Jessup, employed by a company in Italy, is transferring to a subsidiary in Japan. The application that holds his personnel information must delete this information from its Oracle database in Italy and add it to its Rdb database in Japan. Both of these operations must be complete or the data about this employee will be "lost in cyberspace." With DECdtm, such an error will not happen.

The DECdtm services are embedded in the OpenVMS operating system. No separate license is required.