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Atomicity does not behave completely orthogonally with regard to the other ACID properties of transactions. For example, isolation relies on atomicity to roll back the enclosing transaction in the event of an isolation violation such as a deadlock; consistency also relies on atomicity to roll back the enclosing transaction in the event of a consistency violation by an illegal transaction.
An atomic system must guarantee atomicity in each and every situation, including power failures, errors, and crashes. [4] A guarantee of atomicity prevents updates to the database from occurring only partially, which can cause greater problems than rejecting the whole series outright.
In computer science, write-ahead logging (WAL) is a family of techniques for providing atomicity and durability (two of the ACID properties) in database systems. [1]A write ahead log is an append-only auxiliary disk-resident structure used for crash and transaction recovery.
This means the same problems identified in the example have reoccurred. Any algorithmic solution to this problem will still encounter the Two Generals’ Problem. The two-phase commit protocol and three-phase commit protocol attempt to solve this and some of the other problems associated with atomic commits.
In computer science, shadow paging is a technique for providing atomicity and durability (two of the ACID properties) in database systems. A page in this context refers to a unit of physical storage (probably on a hard disk), typically of the order of 1 to 64 KiB. Shadow paging is a copy-on-write technique for avoiding in-place updates of pages.
Atomicity (database systems), a property of database transactions which are guaranteed to either completely occur, or have no effects; Atomicity (programming), an operation appears to occur at a single instant between its invocation and its response; Atomicity, a property of an S-expression, in a symbolic language like Lisp
Isolation is typically enforced at the database level. However, various client-side systems can also be used. It can be controlled in application frameworks or runtime containers such as J2EE Entity Beans [2] On older systems, it may be implemented systemically (by the application developers), for example through the use of temporary tables.
Thus concurrency control is an essential element for correctness in any system where two database transactions or more, executed with time overlap, can access the same data, e.g., virtually in any general-purpose database system. Consequently, a vast body of related research has been accumulated since database systems emerged in the early 1970s.