Journal ArticleDOI
The notions of consistency and predicate locks in a database system
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TLDR
It is argued that a transaction needs to lock a logical rather than a physical subset of the database, and an implementation of predicate locks which satisfies the consistency condition is suggested.Abstract:
In database systems, users access shared data under the assumption that the data satisfies certain consistency constraints. This paper defines the concepts of transaction, consistency and schedule and shows that consistency requires that a transaction cannot request new locks after releasing a lock. Then it is argued that a transaction needs to lock a logical rather than a physical subset of the database. These subsets may be specified by predicates. An implementation of predicate locks which satisfies the consistency condition is suggested.read more
Citations
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Proceedings ArticleDOI
Proving Consistency Of Database Transactions
G. Gardarin,M. Melkanoff +1 more
TL;DR: An approach for verifying that explicitely stated integrity constraints are not violated by certain transactions is presented, utilizing a relational model where-in constraints are given in a language based on the first order predicate calculus.
Proceedings ArticleDOI
Queueing network models for concurrent transaction processing in a database system
Keki B. Irani,Hing-Lung Lin +1 more
TL;DR: These results confirm the result of Ries and Stonebraker, using a simulation model, that a relatively coarse granularity is sufficient to allow enough parallelism for efficient resource utilization and examine more closely the cause-effect relationships of concurrent transaction processing in a database system at less cost.
Journal ArticleDOI
Commutativity-based locking for nested transactions
TL;DR: A new model for describing and reasoning about transaction-processing algorithms is presented, which provides a comprehensive, uniform framework for rigorous correctness proofs and general conditions for a concurrency control algorithm to be correct-i.e., to ensure that transactions appear to be atomic.
Proceedings ArticleDOI
Concepts for transaction recovery in nested transactions
Theo Haerder,Kurt Rothermel +1 more
TL;DR: A model for nested transaction is introduced allowing for synchronous and asynchronous transaction invocation as well as single call and conversational interfaces and properties and dependencies of transaction recovery are explored if a transaction is 'unit of recovery' and if savepoints within transactions are used to gain finer recovery units.
References
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Journal ArticleDOI
A relational model of data for large shared data banks
TL;DR: In this article, a model based on n-ary relations, a normal form for data base relations, and the concept of a universal data sublanguage are introduced, and certain operations on relations are discussed and applied to the problems of redundancy and consistency in the user's model.
Proceedings ArticleDOI
Recovery semantics for a DB/DC system
TL;DR: A unified, systematic view of integrity/recovery as it relates to a data-processing system—whether man, machine, or both is presented.
Proceedings ArticleDOI
Recovery scenario for a DB/DC system
TL;DR: Previously developed sphere-of-control (SOC) concepts are used to develop a scenario for post-process recovery where an information structure provides the recovery boundary around the effects of the usage of a resource.