Journal ArticleDOI
The notions of consistency and predicate locks in a database system
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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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Patent
Concurrency and recovery for index trees with nodal updates using multiple atomic actions
David B. Lomet,Betty Salzberg +1 more
TL;DR: In this article, an approach to index tree structure changes which provides high concurrency while being usable with many recovery schemes and with many varieties of index trees is presented. But this approach does not support multiple concurrent structure changes and only data node splitting executes in the context of a database transaction.
Book
Distributed transactions for reliable systems
TL;DR: The paper describes a prototype transaction facility, called TABS, that supports objects, transparent communication, synchronization, recovery, and transaction management and concludes that the prototype provides useful facilities, and that it would be feasible to build a high performance implementation based on its ideas.
Proceedings ArticleDOI
The complexity of testing predicate locks
TL;DR: The problem of testing predicates for satisfiability arises in several aspects of database systems such as the use of predicate locks in concurrency control and the proofs involve showing that if a predicate is satisfiability, then it is satisfiable by a tuple whose field values are related to constants occurring in the predicate.
Proceedings ArticleDOI
Recovery-management in the RelaX distributed transaction layer
TL;DR: The new commit/abort protocols will be used in the RelaX project (reliable distributed applications support on Unix), which carries on work done at GMD in the PROFEMO project on distributed transaction mechanisms.
Proceedings ArticleDOI
Concurrency in database systems: a simulation study
Rudolf Munz,Gunter Krenz +1 more
TL;DR: A simulation model of concurrent updates in a database system is presented to answer the following questions: How frequent are deadlocks in certain environments?
References
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Proceedings ArticleDOI
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Proceedings ArticleDOI
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