Durability (database systems)

Durability (database systems)

In database systems, durability is the ACID property which guarantees that transactions that have committed will survive permanently. For example, if a flight booking reports that a seat has successfully been booked, then the seat will remain booked even if the system crashes.

Durability can be achieved by flushing the transaction's log records to non-volatile storage before acknowledging commitment.

In distributed transactions, all participating servers must coordinate before commit can be acknowledged. This is usually done by a two-phase commit protocol.

Many DBMSs implement durability by writing transactions into a transaction log that can be reprocessed to recreate the system state right before any later failure. A transaction is deemed committed only after it is entered in the log.

See also



Wikimedia Foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • Isolation (database systems) — In database systems, isolation is a property that defines how/when the changes made by one operation become visible to other concurrent operations. Isolation is one of the ACID (Atomicity, Consistency, Isolation, Durability) properties.Isolation… …   Wikipedia

  • Consistency (database systems) — In database systems, a consistent transaction is one that does not violate any integrity constraints during its execution. If a transaction leaves the database in an illegal state, it is aborted and an error is reported.Consistency is one of the… …   Wikipedia

  • Durability — is the ability to endure. It can refer to: Durable goods, goods with a long usable life in economics. Durability (database systems), one of the ACID properties. In safety and technology: Dust resistant Fire resistant Rot proof Rustproof Thermal… …   Wikipedia

  • Atomicity (database systems) — In database systems, atomicity (or atomicness) is one of the ACID transaction properties. In an atomic transaction, a series of database operations either all occur, or nothing occurs. A guarantee of atomicity prevents updates to the database… …   Wikipedia

  • Database — A database is an organized collection of data for one or more purposes, usually in digital form. The data are typically organized to model relevant aspects of reality (for example, the availability of rooms in hotels), in a way that supports… …   Wikipedia

  • In-memory database — An in memory database (IMDB; also main memory database system or MMDB) is a database management system that primarily relies on main memory for computer data storage. It is contrasted with database management systems which employ a disk storage… …   Wikipedia

  • Distributed database — A distributed database is a database in which storage devices are not all attached to a common CPU. It may be stored in multiple computers located in the same physical location, or may be dispersed over a network of interconnected computers.… …   Wikipedia

  • Microsoft Jet Database Engine — This article is about JET Red used in Microsoft Access. For the JET Blue ISAM implementation, see Extensible Storage Engine. The Microsoft Jet Database Engine is a database engine on which several Microsoft products have been built. A database… …   Wikipedia

  • Enterprise database management — system requires enterprises to evaluate their data Management strategies and enable them to manage relentless data growth and regulatory compliances which are a crucial foundation for the unwired enterprise.The goal of enterprise database is to… …   Wikipedia

  • ACID — For other uses, see Acid (disambiguation). In computer science, ACID (atomicity, consistency, isolation, durability) is a set of properties that guarantee database transactions are processed reliably. In the context of databases, a single logical …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”