Concurrency control is the activity of synchronizing database operations by concurrently executing transactions on a shared database. We examine the problem of concurrency control when the database supports multiple versions of the data. Multiversion concurrency control is used in order to improve the level of achievable concurrency. The goal is to produce an execution that has the same effect as a serial one. We use the multiversion concurrency control theory to analyze histories produced by multiversion concurrency control methods. We show that using traditional repeatable read isolation level is inadequate and provide a new isolation level definition for multiversion repeatable read. We show that the new isolation level captures the essence of repeatable read isolation level in multiversioning systems.

A real-time database system (RTDBS) is a database system providing all features on traditional database system such as data independence and concurrency control, while at the same time enforces real-time constraints that applications may have [13]. Like a traditional database system, a RTDBS functions as a repository

Experimental demonstration of a silicon-on-insulator high-performance double

Abstract not found

Demonstrates how the infrastructure of IBM TotalStorage, eServer pSeries, LTO, and SAN can facilitate regulatory compliance Uses a sample method to help meet the qualification requirements of FDA 21 CFR Part 11 Shows sample documentation to help meet compliance standards International Technical

Extractors and taggers turn unstructured text into entityrelation (ER) graphs where nodes are entities (email, paper, person, conference, company) and edges are relations (wrote, cited, works-for). Typed proximity search of the form type=person NEAR company∼"IBM", paper

from the Israel Science Foundation administered by the Israeli Academy of Sciences. Most of this work was done while the author was at the IBM Almaden Research Center. y Most of this work was done while the author was with Bellcore. 1 Introduction Consider the following problem, which actually

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. With current design methods, hundreds to thousands of bugs must be found and removed during the design of a new processor, and there are heavy economic incentives to get most of them out before first silicon. Current designs are so complex that simulation-based methods are no longer adequate. Most companies

I declare that this report is my own original work and that no part of it has been submitted to any other institute of learning in support of an application for another award. No other sources than those quoted have been used. The opinions expressed in the report are put forward in a personal capacity and do not represent those of the University of Koblenz or any organisation with which the author may be associated. Signature................................. Date.................................