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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Introducing self-adaptability into transaction processing
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False Deadlock Detection in Distributed Systems
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Network latency optimizations in distributed database systems
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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.