"An approach for maintaining consistency over multiple systems. In the first phase, all backends are asked to confirm a requested change so that in the second phase the commitment of the updates usually succeeds." (Nicolai M Josuttis, "SOA in Practice", 2007)
"A protocol that ensures that transactions that apply to more than one server are completed on all servers or on none." (Microsoft Corporation, "SQL Server 7.0 System Administration Training Kit", 1999)
"A mechanism to synchronize updates on different machines or platforms, so that they all fall or all succeed together. The decision to commit is centralized, but each participant has the right to veto. This is a key process in real-time, transaction-based environments." (Atul Apte, "Java™ Connector Architecture: Building Custom Connectors and Adapters", 2002)
"A process that ensures transactions that apply to more than one server are completed on all servers or on none." (Anthony Sequeira & Brian Alderman, "The SQL Server 2000 Book", 2003)
"This is a special transaction involving two servers in which the transaction must be applied to both servers, or the entire transaction is rolled back from both servers." (Joseph L Jorden & Dandy Weyn, "MCTS Microsoft SQL Server 2005: Implementation and Maintenance Study Guide - Exam 70-431", 2006)
"A transaction processing protocol that first ensures the transaction holds locks on all records involved before committing any updates." (DAMA International, "The DAMA Dictionary of Data Management", 2011)
"A protocol that ensures that transactions that apply to more than one server are completed on all servers or none at all. Two-phase commit is coordinated by the transaction manager and supported by resource managers." (Microsoft, "SQL Server 2012 Glossary", 2012)
"A two-step process by which recoverable resources and an external subsystem are committed. During the first step, the database manager subsystems are polled to ensure that they are ready to commit. If all subsystems respond positively, the database manager instructs them to commit." (IBM, "Informix Servers 12.1", 2014)
"A mechanism that is another control used in databases to ensure the integrity of the data held within the database." (Adam Gordon, "Official (ISC)2 Guide to the CISSP CBK" 4th Ed., 2015)
"A two-step process by which recoverable resources and an external subsystem are committed. During the first step, the database manager subsystems are polled to ensure that they are ready to commit. If all subsystems respond positively, the database manager instructs them to commit. See also distributed transaction." (Sybase, "Open Server Server-Library/C Reference Manual", 2019)
"A feature of transaction processing systems that enables a database to be returned to the pretransaction state if an error condition occurs." (Craig S Mullins, "Database Administration: The Complete Guide to DBA Practices and Procedures", 2012)
"A process that ensures transactions that apply to more than one server are completed on all servers or on none." (Microsoft Technet)
"An operation that is part of a distributed transaction, under the XA specification. (Sometimes abbreviated as 2PC.) When multiple databases participate in the transaction, either all databases commit the changes, or all databases roll back the changes." (MySQL, "MySQL 8.0 Reference Manual Glossary")
"The process of committing a distributed transaction in two phases. In the first phase, the transaction processor checks that all parts of the transaction can be committed. In the second phase, all parts of the transaction are committed. If any part of the transaction indicates in the first phase that it cannot be committed, the second phase does not occur. ODBC does not support two-phase commits." (Microsoft, "ODBC Glossary")
