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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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Value-cognizant Speculative Concurrency Control

TL;DR: SCC-kS, a Speculative Concurrency Control algorithm that allows a DBMS to use efficiently the extra computing resources available in the system to increase the likelihood of timely commitment of transactions, and SCC-DC, a value-cognizant SCC protocol that utilizes deadline and criticalness information to improve timeliness through the controlled deferment of transaction commitments.

Live Database Migration for Elasticity in a Multitenant Database for Cloud Platforms

TL;DR: This work proposes an efficient technique for live migration of a tenant’s database with minimal downtime and impact on performance and implements the proposed technique in a database system designed for the cloud.

Efficient Reliable Group Communication for Distributed Systems

TL;DR: This paper introduces primitives for broadcast communication that have been integrated with the Amoeba distributed operating system and introduces semantics of the broadcast primitives that guarantee total ordering of broadcast messages.
Proceedings ArticleDOI

Specification and implementation of resilient, atomic data types

TL;DR: This work defines what it means for abstract data types to be atomic and resilient, and discusses issues that arise in implementing such types, and describes a particular linguistic mechanism provided in the Argus programming language.
Proceedings Article

Adaptive Locking Strategies in a Multi-node Data Sharing Environment

Ashok Joshi
TL;DR: Some of the concurrency control 1” lgorithms used in RdMVMS RdbIVMS uses the facilities provided by the VMS lock manager in order to perform locking among concurrent processes to reduce the 1ockinR overhead considerably.
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.