Index scans using a finite LRU buffer: a validated I/O model

In recent past, the bookstores generate more data such as customer details, transaction details, book details, etc. for analyzing them to make data-driven decisions. These data are stored in a centralized database. In centralized database system, the data are stored in a single site or location and that are managed. The major drawback is that if the centralized system gets crashed the entire data are lost and also it makes access bottleneck when more users need to access the database. In order to overcome these limitations, the distributed database system is used to store the business data by locating them in different databases that are located in different sites in different location. The distributed database maintains the replication and duplication that ensure the availability and fault tolerance on the data. The distributed system also provides the high accessibility to the users. Thus, this paper presents a distributed database for a bookstore to improve availability, fault tolerance, and accessibility. This distribution also maintains the transparency and supports the database properties such as atomicity, consistency, inheritance and durability (ACID). Furthermore, this distributed database is designed with four sites and each site keeps the bookstore data for access and analyses. This distributed database is constructed and accessed using structured query language (SQL) with MySQL relational database management system (RDBMS). It also provides the security and work even in offline mode. Keywords: distributed databases; query processing; relational database management; structured query language; bookstore database;

The authors describe the Distributed Information Storage Architecture (DISA) defined and prototyped at Hewlett-Packard by the Networked Systems Architecture organization. In the first phase of the project, an architecture framework was defined that isolated storage-management functions from database and file-management systems. The idea was to identify and encapsulate functions related to the persistent characteristics of stored data. Only functions common to a large variety of database and file-management systems were of interest. The intent was to build a new storage-management base without altering file or database systems. To validate this idea, a storage-management prototype called StoragePlus was built. The StoragePlus prototype automated several storage-management and administration functions currently done manually. It also demonstrated how one could reduce and control storage administrative costs by doing central administration of distributed storage across a network.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Application of SLAM in the design and performance analysis of a multi-processor database system

In database and information systems, increasing attention has been focused lately on parallel and distributed database systems. The future of large database systems lies into the realm of distributed computing. The main reason for this is that distributed computing can be constructed at a low cost without the need for any specialized technology, using existing sequential computers and relatively cheap computer networks. The basic motivations for distributed databases are improved performance, increased availability, share ability, expandability, and access flexibility. Oracle9i is one of the most famous database management systems that provide distributed features. Oracle9i supports transparent distributed gains to access data from multiple databases. It also provides many other distributed features, such as transparent distributed transactions and transparent automatic two-phase commit. This paper presents a distributed registration database system using Oracle9i distributed features such as replication and fragmentation. The analysis and design steps of the distributed registration database system are shown as well as to the practical steps required for implementing the distributed database system using Oracle9i.

With the development of society and the arrival of the information age, data processing has become more and more complex, so people need to manage data systems through wireless communication, and distributed systems can effectively improve data analysis, so this paper is based on wireless communication. Distributed database systems are studied. With the rapid development of database systems, how to effectively obtain useful information about massive data has gradually become an important research problem of/with the field of data management. The purpose of this paper is to study how to research the data processing of distributed parallel database system based on wireless network. This paper puts forward the basic concepts of wireless network and distributed parallel database system and proposes a clustering analysis algorithm. The preimproved clustering analysis and the improved distributed parallel clustering analysis are described and compared in detail. From the data in the figure in the experimental part of the text, it can be seen that the efficiency of the database system before the improvement is the lowest at 41% and the highest at 58%. The efficiency of the improved distributed database system is at least 65%, and the highest are 95%. It can be seen that the efficiency of the improved distributed database system is much higher than that of the preimproved database system. So it is very feasible to use the distributed database system to process data.

The design of the logical structure of databases using the entity-relationship (E-R) model is considered. The goal is to focus on E-R conditions for desirable logical design, using an extended translation of the full E-R model into the more easily implementable relational database model; all entity sets in a regular E-R diagram will map to relation schemes that are in the very desirable Boyce-Codd normal form (BCNF). Conditions under which extended E-R relationship sets translate to BCNF schemes are found. These results extend to both types of weak entity sets, subset and dependent entity sets, and contribute to the logical design of robust database systems. An E-R-diagram-based design system currently under development enforces the conditions that ensure BCNF by ensuring extended regularity and other measures of well-behaved E-R models. >

Distributed heterogeneous integrates asset of autonomous database systems to provide global database functions. The client/server-based distributed heterogeneous database system has a limited concurrency and scalability. In this paper, we proposed a new distributed heterogeneous database system model based on intelligent agent approach. In this model, we implement the functions of the system using agent approach. We defined several agents, such as, UIagent, Transagent, GIagent, parti-agent, coord-agent, etc. We discussed the transaction processing process and discussed the ACID properties of the transaction. This model can farthest develop the concurrency of the transaction and it is suitable for the large scale distributed heterogeneous database system.

Database systems are widely used in many fields. As the scale of database systems increases, more firms decide to deploy the database system in a distributed environment for the sake of data integrity fault tolerance. For guaranteeing the consistency of data, database management systems adopt isolation policies. This paper discusses probabilistic models for snapshot isolation of database management system. Snapshot isolation is an effective method to enhance the consistency of database system, although it degrades the system performance where the system has large network latency such as distributed database system. Also, under the failure-prone environment, a restart scheme is considered as one countermeasure. This paper proposes probabilistic models for the dynamics of snapshot isolation of database system and exhibits the optimization of system performance with respect to updating interval of snapshot isolation within the failure-prone environment from the analytical point of view. Numerical experiments are conducted to validate the effectiveness of analytical results by using real traffic data.

Data access in distributed data base management systems

The GSM Recommendations give the standards for a Pan-European mobile radio telecommunication system. The Location Registers form a Distributed Data Base whose interworking with other entities of the GSM System provides an integrated directory function. The properties and functionality of the GSM Location Registers and the implementation of the Distributed Data Base in the system “ECR 900” are described.

Logical design of data base systems

Data allocation issue is one of the significant and essential discussions in distributed data base systems. In these systems, operators are located in different places and have to get access to a joint data base. These data have been distributed within the network. Many models have been designed in order to resolve this problem. Also, some algorithms are devised for the purpose of decreasing data transferring expense and decreasing the time of responding. The most important expense belongs to data transferring. This cost equals to a query's access to the required data from different sites to the place in which the query has been produced. In this article, we deal with modularization algorithms which make data transferring expense reduce during a query execution. These algorithms accomplish this by optional modularization of the sites in which the data are located.

Consider the class of distributed database systems consisting of a set of nodes connected by a high bandwidth network. Each node consists of a processor, a random access memory, and a slower but much larger memory such as a disk. There is no shared memory among the nodes. The data are horizontally partitioned often using a hash function. Such a description characterizes many parallel or distributed database systems that have recently been proposed, both commercial and academic. We study the optimization problem that arises when the query processor must repartition the relations and intermediate results participating in a multijoin query. Using estimates of the sizes of intermediate relations, we show (1) optimum solutions for closed chain queries; (2) the NP-completeness of the optimization problem for star, tree, and general graph queries; and (3) effective heuristics for these hard cases. Our general approach and many of our results extend to other attribute partitioning schemes, for example, sort-partitioning on attributes, and to partitioned object databases.

The Polar project has the aim of designing a parallel, ODMG compatible object database server. This paper describes the server requirements and investigates issues in designing a system to achieve them. We believe that it is important to build on experience gained in the design and usage of parallel relational database systems over the last ten years, as much is also relevant to parallel object database systems. Therefore we present an overview of the design of parallel relational database servers and investigate how their design choices could be adopted for a parallel object database server. We conclude that while there are many similarities in the requirements and design options for these two types of parallel database servers, there are a number of significant differences, particularly in the areas of object access and method execution.

The transition to digital channels and maximum digitalization of the business of modern companies in the energy sector dictate the need to improve and develop new approaches to design and database management. The study aims to identify innovative aspects in the design and management of database systems. To achieve these goals, key aspects of database design are emphasized through the argumentation of the data modeling process. Modern types of database models are identified and the need to normalize data and get rid of their redundancy is argued. The main components of the company database management system are structured. The structure of the decision support system processes is proposed. A sequence of operations with the database has been developed in the case of registration/purchase of goods using online platforms. The structure of information systems of modern companies is highlighted with an emphasis on the main functions of database management systems, taking into account the growth of digital technologies and channels of interaction with customers. The developed approaches can be applied in practice as the basis for the theory of design and management of data warehouses, taking into account innovative aspects of development.