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occur. A guarantee of atomicity prevents partial database updates from occurring, because they can cause greater problems than rejecting the whole series outright. As a consequence, the transaction cannot be observed to be in progress by another database client. At one moment in time, it has not yet
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An example of an atomic transaction is a monetary transfer from bank account A to account B. It consists of two operations, withdrawing the money from account A and saving it to account B. Performing these operations in an atomic transaction ensures that the database remains in a
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in database systems, where it instead refers to the concept that the values for fields may not consist of multiple smaller values to be decomposed, such as a string into which multiple names, numbers, dates, or other types may be packed.
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An operation during which a processor can simultaneously read a location and write it in the same bus operation. This prevents any other processor or I/O device from writing or reading memory until the operation is
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Typically, systems implement
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As a result of this, a failure to detect a violation and roll back the enclosing transaction may cause an isolation or consistency failure.
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also relies on atomicity to roll back the enclosing transaction in the event of a consistency violation by an illegal transaction.
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happened, and at the next it has already occurred in whole (or nothing happened if the transaction was cancelled in progress).
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245:irreducible
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219:Consistency
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471:2016-02-28
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