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Journal ArticleDOI

The notions of consistency and predicate locks in a database system

Kapali P. Eswaran, +3 more
- 01 Nov 1976 - 
- Vol. 19, Iss: 11, pp 624-633
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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.

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Citations
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Absolute and relative temporal constraints in hard real-time databases

TL;DR: The techniques described in this paper can be used to reduce the problem to a single NP-complete scheduling problem, and standard scheduling theory can then be applied.
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Less optimism about optimistic concurrency control

C. Mohan
TL;DR: This paper discusses some of the shortcomings of the optimistic concurrency control (OCC) approach in supporting all the features expected in a full-function DBMS and increases-awareness of the implementation aspects of OCC amongst researchers and initiates a debate about the practical utility of O CC.
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The CORDS multidatabase project

TL;DR: An overview of the system architecture is provided and the approaches taken in the following areas: management of catalog information, schema integration, global query optimization, (distributed) transaction management, and interactions with component data sources are described.
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Resilient Logical Structures for Efficient Management of Replicated Data

TL;DR: The proposed protocols have the advantages of the readone write-all protocol for low cost read operations as well as the majority quorum protocol for high data availability.
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.
Book

Introduction to Metamathematics

H. Rasiowa
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.