Data fragmentation is one of the primary techniques that has been used in partitioning and developing distributed database systems (DDBs). database partitioning technique improves the performance of the system through...
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Data fragmentation is one of the primary techniques that has been used in partitioning and developing distributed database systems (DDBs). database partitioning technique improves the performance of the system throughput and reduces the amount of irrelevant data to be accessed and transferred among different sites in DDBs. We propose a technique that splits the database relations into pair-wise disjoint fragments, which would be allocated to the DDBs sites during the process of allocation. This technique reduces the data transferred between the sites during the applications execution, minimizes the communication cost needed for processing applications, handles the database queries and meets their future needs, guarantees the ability of processing a given portion of a given transaction in all sites, and improves the applications speed and efficiency by minimizing the number of fragments to be accessed. We have also developed a fragmentation tool that is interactive, full functional and easy to use, based on our fragmentation life cycle algorithms to create the database segments and generate the minimum number of disjoint fragments. A case study and some results in tabular and graphical means will be presented to demonstrate the efficiency of the method.
In distributed databases for general-purpose business software, such as groupware, the asynchronous replication update method is widely employed to assure coincidence in the contents of the database;the replications o...
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In distributed databases for general-purpose business software, such as groupware, the asynchronous replication update method is widely employed to assure coincidence in the contents of the database;the replications of other databases retained in each database are updated simultaneously according to a predetermined schedule. This article discusses the approximate scheduling in such a distributed database that minimizes the communications cost of updating the replications, More precisely, as the first step, we consider the case in which two-way concurrent transmission is allowed in each link, and the communications cost is proportional to the communication time required for the transfer. The problem of deriving the schedule to minimize the communications cost is formulated. As a practical method of solving that problem, a heuristic method that effectively derives the approximate schedule with a communications cost close to the minimum is proposed. A quantitative evaluation of the proposed method is presented, and it is shown that a schedule very close to the optimal solution is obtained if the communications cost coefficient of the links is almost the same. (C) 1999 Scripta Technica.
This article describes the sustainable production system made islands. distributed data resources used to produce goods for consumption and disposal. Production activities are supported by global non-critical resource...
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This article describes the sustainable production system made islands. distributed data resources used to produce goods for consumption and disposal. Production activities are supported by global non-critical resources, such as capital, technology and expertise in embedded systems, patents and data: analysis and business plan. Provide a case study to explain this arrangement. Understand the potential of the Island?s manufacturing sector to add value to the debate on sustainable manufacturing. This study aims to develop an embedded system as a model recognized as a highly developed modern development model, and tourism destination as a system bound essentially regional representatives with a specific development framework. Find similarities with the indispensable support of the overall product at your destination for a distributed database server. By this analogy, find a long-term development model suitable for local commercial embedded systems tourist destinations. A reasonable solution is the concept of sustainable development;the basic principle is coherent. Tourism destination management principles function.
As the main factor in the distributed database systems, query optimization is aimed at finding an optimal execution plan to reduce the runtime. In such systems, because of the repeated relations on various sites, the ...
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As the main factor in the distributed database systems, query optimization is aimed at finding an optimal execution plan to reduce the runtime. In such systems, because of the repeated relations on various sites, the query optimization is very challenging. Moreover, the query optimization issue with large-scale distributed databases is an NP-hard problem. Therefore, in this paper, an Artificial Bee Colony Algorithm based on Genetic Operators (ABC-GO) is proposed to find a solution to join the query optimization problems in the distributed database systems. The ABC algorithm has the global-local search capabilities and genetic operators to create new candidate solutions for improving the performance of the ABC algorithm. The obtained results have shown that the cost of the query evaluation is minimized and the quality of Top-K query plans is improved for a given distributed query. Moreover, this method decreases the overhead. However, it needs a longer execution time.
Optimal state information-based control policy for a distributed database system subject to server failures is considered. Faulttolerance is made possible by the partitioned architecture of the system and data redunda...
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Optimal state information-based control policy for a distributed database system subject to server failures is considered. Faulttolerance is made possible by the partitioned architecture of the system and data redundancy therein. Control actions include restoration of lost data sets in a single server using redundant data sets in the remaining servers, routing of queries to intact servers, or overhaul of the entire systemfor renewal. Control policies are determined by solvingMarkov decision problems with cost criteria that penalize system unavailability and slow query response. Steady-state system availability and expected query response time of the controlled database are evaluated with the Markov model of the database. Robustness is addressed by introducing additional states into the database model to account for control action delays and decision errors. A robust control policy is solved for the Markov decision problem described by the augmented state model. Copyright (C) 2008 N. EvaWu et al.
A big database utilizes the establishing network technology, and it became an emerging trend in the computing field. Therefore, there is a necessity for an optimal and effective data distribution approach to deal with...
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A big database utilizes the establishing network technology, and it became an emerging trend in the computing field. Therefore, there is a necessity for an optimal and effective data distribution approach to deal with this trend. This research presents the practical perspective of designing and implementing distributed database features. The proposed system has been establishing the satisfying, reliable, scalable, and standardized use of information. Furthermore, the proposed scheme reduces the vast and recurring efforts for designing an individual system for each university, as well as it is effectively participating in solving the course equivalence problem. The empirical finding in this study shows the superiority of the distributed system performance based on the average response time and the average waiting time than the centralized system. The system throughput also overcomes the centralized system because of data distribution and replication. Therefore, the analyzed data shows that the centralized system thrashes when the workload exceeds 60%, while the distributed system becomes thrashes after 81% workload.
distributed databases in general-purpose business software such as groupware widely use a method for simultaneously updating the replicas of other databases owned by each database according to the replication routing ...
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distributed databases in general-purpose business software such as groupware widely use a method for simultaneously updating the replicas of other databases owned by each database according to the replication routing schedule. In this paper, a replication routing schedule is discussed in which the time required for updating the replica is the minimum in the distributed database. Specifically, an optimization problem is first formulated for deriving the replication routing schedule with minimum update time. Next, in the cases of even and odd numbers of distributed databases, an algorithm providing a replication routing schedule as an optimum solution is presented in the even case, while a heuristic algorithm providing an approximate solution is shown for the odd case. These algorithms are extremely simple and are practical since the required amount of computational processing is small. (C) 1998 Scripta Technica, Electron Comm Jpn Pt 1, 82(2): 11-20, 1999.
With the growth of information technology and computer networks, there is a vital need for optimal design of distributed databases with the aim of performance improvement in terms of minimizing the round-trip response...
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With the growth of information technology and computer networks, there is a vital need for optimal design of distributed databases with the aim of performance improvement in terms of minimizing the round-trip response time and query transmission and processing costs. To address this issue, new fragmentation, data allocation, and replication techniques are required. In this paper, we propose enhanced vertical fragmentation, allocation, and replication schemes to improve the performance of distributed database systems. The proposed fragmentation scheme clusters highly-bonded attributes (i.e., normally accessed together) into a single fragment in order to minimize the query processing cost. The allocation scheme is proposed to find an optimized allocation to minimize the round-trip response time. The replication scheme partially replicates the fragments to increase the local execution of queries in a way that minimizes the cost of transmitting replicas to the sites. Experimental results show that, on average, the proposed schemes reduce the round-trip response time of queries by 23% and query processing cost by 15%, as compared to the related work.
distributed databases Systems (DDBS) are a set of logically networked computer databases, managed by different sites, locations and accessible to the user as a single database. DDBS is an emerging technology that is u...
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distributed databases Systems (DDBS) are a set of logically networked computer databases, managed by different sites, locations and accessible to the user as a single database. DDBS is an emerging technology that is useful in data storage and retrieval purposes. Still, there are some problems and issues that degrade the performance of distributed databases. The Aim of this paper is to provide a novel solution to distributed database problems that is based on distributed database challenges collected in one diagram and on the relationship among DDB challenges in another diagram. This solution presents two methodologies for distributed databases management Systems: deep learning-based fragmentation and allocation, and blockchain technology-based security provisioning. The contribution of this paper is twofold. First, it summarizes major issues and challenges in the distributed database. Additionally, it reviews the research efforts presented to resolve the issues. Secondly, this paper presents a distributed database solution that resolves the major issue of distributed database technology. This paper also highlights the future research directions that are appropriate for distributed database technology after the implementation in a large-scale environment and recommended the technologies that can be used to ensure the best implementation of the proposed solution.
The problem of traditional distributed database implementation in real-time control is discussed. According to features of data in real-time control distributed system, a enhanced performance design model (EPADM) of d...
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The problem of traditional distributed database implementation in real-time control is discussed. According to features of data in real-time control distributed system, a enhanced performance design model (EPADM) of distributed database control is presented. Lastly, measurement analysis and some appraizement on EPADM is gived.
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