two-phase commit


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two-phase commit

(database)
A technique for maintaining integrity in distributed databases. Where a system uses two or more database, a transaction among the distibuted database should be atomic ("all or nothing"). This is done by handling the transaction in two phases. First the databases prepare the transaction, confirm that it is possible to process it, and lock the relevant record.

Once all the required databases confirm that the transaction is viable, the system instructs them all to commit it - i.e. to make it permanent. If it is not possible to process it, the system will instruct the databases to rollback (undo) the transaction.

two-phase commit

A technique for ensuring that a transaction successfully updates all appropriate files in a distributed database environment. All DBMSs involved in the transaction first confirm that the transaction has been received and is recoverable (stored on disk). Then each DBMS is told to commit the transaction (do the actual updating).

Traditionally, two-phase-commit meant updating databases in two or more servers, but the term is also applied to updating two or more different databases within the same server. See transaction, transaction file and transaction processing.
References in periodicals archive ?
The kinds of failure were interested in for this example are those that occur after the participants in the two-phase commit transaction have said they will do the work requested of them (transfer the money) i.
As long as the available bandwidth is equal or greater to the rate of data change, data will be transmitted and applied almost instantaneously providing "near zero" data loss without the round-trip delay overhead associated with synchronous mirroring or two-phase commit.
The decision to abort is implemented in the same way as the two-phase commit protocol.
It offers a review of distributed computing fundamentals, an overview of the Jini architecture, and an introduction to the key concepts that are the source of the technology's simplicity and power: remote objects, leasing, distributed events, and a two-phase commit protocol.
The upgrade offers a two-phase commit capability, enabling users to interact with data in multiple databases on multiple host platforms.
Unlike most remote backup systems, Intellibuffer performs a two-phase commit between the remote and local appliance to verify that the data write is correct.
Enhanced EJB transaction support with full two-phase commit VisiTransact?