Client-server Database Systems Research Articles

Haversine Formula and RPA Algorithm for Navigation System

The system uses a geographic information system to analyze and monitor traffic congestion and use GPS data for public transport planning in Yangon, Myanmar. The system provides accurate maps for estimating traffic conditions more efficiently from GPS data, saving more time. The proposed system displays changes in the position, distance and direction of vehicles traveling on the streets of Yangon by using traffic state and routing pattern algorithm. There established centralized GPS server database infrastructure provides any kind of analysis that requires GPS traffic data stored in a distributed client-server environment. In this system, a statement of user desired traffic jams between the source and destination is estimated and the results are presented with a Map. This system is for analyzing traffic data, avoiding traffic congestion and obtaining optimal routes with a modified A* algorithm. GPS data (current location) and user search area using the K-d tree and Haversine algorithm are required. Second, look for traffic jam data with Google's traffic layer and the routing matrix pattern algorithm. Finally, Analysis the traffic by Smart-A* and then show the result of traffic congestion statement and best optimal route. In the case, there are three main components: Data Collection, Data Extraction and Implementation. And this is Client-Server database system that storing the data and server in the cloud Virtual Machine (VM).

DESAIN SISTEM PENDATAAN KEHADIRAN KARYAWAN TERINTEGRASI FINGERPRINT DENGAN FUNGSI PENGATURAN SHIFT KERJA BERBASIS VISUAL

Data collection on employee attendance at a company is a must, with the aim of monitoring discipline, calculating employee salaries, and other needs. Data collection on employee attendance at companies that are used today is very diverse, following the development of technology. The United Tronik Semarang office, which employs relatively many employees, currently uses a manual card attendance data collection system that attracts researchers to make the United Tronik Office the object of research.
 Fingerprint is one of the hardware used to support employee attendance data collection which is relatively simple and easy to reach, the accuracy and ease of operation make the fingerprint attendance system more and more in demand. One of the human error problems in the attendance data collection system is attendance recording errors, especially for employees with shift work hours. Arrangement of work shifts in programs built with Visual Basic 2010 can minimize attendance recording errors, because it can set the recording time for employees. To support the ease of data access and shift settings, the researcher uses a Client Server database system with SQL Server 2005 Software.

A Compressed Technique to Optimize the Processing of Real Time Data in Centralized and Client-Server Data Base Systems

The processing of real time transaction is an important issue in present scenario. It depends on various constraints of architecture such as data size, bandwidth speed, network latency and machine configuration etc. The present paper proposes a mathematical model to improve in the response time in centralized and client-server paradigm. The work also shows the improvement through simulation done in MatLabR2014.

B-tree concurrency control and recovery in page-server database systems

We develop new algorithms for the management of transactions in a page-shipping client-server database system in which the physical database is organized as a sparse B-tree index. Our starvation-free fine-grained locking protocol combines adaptive callbacks with key-range locking and guarantees repeatable-read-level isolation (i.e., serializability) for transactions containing any number of record insertions, record deletions, and key-range scans. Partial and total rollbacks of client transactions are performed by the client. Each structure modification such as a page split or merge is defined as an atomic action that affects only two levels of the B-tree and is logged using a single redo-only log record, so that the modification never needs to be undone during transaction rollback or restart recovery. The steal-and-no-force buffering policy is applied by the server when flushing updated pages onto disk and by the clients when shipping updated data pages to the server, while pages involved in a structure modification are forced to the server when the modification is finished. The server performs the restart recovery from client and system failures using an ARIES/CSA-based recovery protocol. Our algorithms avoid accessing stale data but allow a data page to be updated by one client transaction and read by many other client transactions simultaneously, and updates may migrate from a data page to another in structure modifications caused by other transactions while the updating transaction is still active.

Efficient Processing of Client Transactions in Real-Time

In traditional client-server databases, a transaction and its requisite data have to be colocated at a single site for the operation to proceed. This has usually been achieved by moving either the data or the transaction. However, the availability of high-bandwidth networking options has led users of today's systems to expect real-time guarantees about the completion time of their tasks. In order to offer such guarantees in a client-server database system, a transaction should be processed by any means that allows it to meet its deadline. To this end, we explore the option of moving both transactions and data to the most promising sites for successful completion. We propose a load-sharing framework that oversees the shipment of data and transactions so as to increase the efficiency of a cluster consisting of a server and a number of clients. Here, efficiency is defined as the percentage of transactions successfully completed within their deadlines by the cluster. The suitability of a client for processing a transaction is measured with respect to the availability of the transaction's required data in its local cache. In addition to the load-sharing algorithm, we use the concept of grouped locks, along with transaction deadline information, in order to schedule the movement of data objects in the cluster in a more efficient manner. We evaluate the real-time processing performance of the client-server architecture using detailed experimental testbeds. Our evaluation indicates that it is possible, in many situations, to achieve better performance than a centralized system.

ADEPT-The Advanced Database Environment for Planning and Tracking

The Advanced Database Environment for Planning and Tracking (ADEPT) is a system that provides the ability to define and manage process definitions. These predefined definitions can be instantiated to create project plans. In managing such plans, ADEPT ensures adherence to predefined process definitions. Unlike most commercial project planning systems, project plans in ADEPT can include information that is tracked across multiple projects. In addition, ADEPT provides the ability to track other kinds of project details besides simple task information and milestone dates. It supports both operational (that is, day-to-day) management of single projects and strategic management of information that crosses project boundaries. It was built on top of a commercial client-server relational database system and uses the standard Structured Query Language (SQL) to model process definitions as object-oriented semantic networks. ADEPT features include real-time reporting, generation of HyperText Markup Language (HTML) reports, report subscription, tracking of quality records, e-mail notification of database transactions, and authorization access control.

Adaptive Transaction Management Protocols for Mobile Client Caching DBMSs

In mobile client-server database systems, caching of frequently accessed data is an important technique that will reduce the contention on the narrow bandwidth wireless channel. As the server in mobile environments may not have any information about the state of its clients' cache (stateless server), the use of a broadcast approach to transmit the list of updated data to numerous concurrent mobile clients is an attractive approach. In this paper, two caching methods are proposed to support transaction semantics at mobile clients. Proposed protocols adopt asynchronous broadcasting and hybrid broadcasting as the way of sending control messages, in order to dynamically adapt to system workload (update pattern, data locality). We study the performance of the proposed protocols by means of simulation experiments.

ADAPTIVE CONCURRENCY CONTROL SCHEMES SUPPORTING MOBILE CLIENT CACHING

In mobile client-server database systems, caching of frequently accessed data is an important technique that will reduce the contention on the narrow bandwidth wireless channel. As the server in mobile environments may not have any information about the state of its clients' cache(stateless server), using broadcasting approach to transmit the list of updated data to numerous concurrent mobile clients is an attractive approach. In this paper, two caching methods are proposed to support transaction semantics at mobile clients. Proposed protocols adopt asynchronous broadcasting and adaptive broadcasting as the way of sending invalidation reports, in order to dynamically adapt to system workload(update pattern, data locality). We study the performance of the proposed protocols by means of simulation experiments.

Parallel Database Techniques

Parallel Database Techniques

A new framework for handling mobile clients in a client–server database system

Mobile computing is a new emerging paradigm that enables mobile computers to access information regardless of their physical location. Data management in this paradigm poses many challenging problems to the database community. One of these research problems is disconnection management. While in the case of file systems there are already decent implementations of systems that support disconnected operation allowing mobile clients to continue their work in the absence of the connection to the server, in the case of database systems the majority of the issues regarding the support for disconnected operation are still open research problems. In this paper we propose a new framework for handling mobile clients in a client–server database system. In order to support disconnected operation data must be preloaded into the mobile client's cache. This process, called data hoarding, is essential since the mobile client can use during disconnections only the data cached locally.

Efficient Mobile Client Caching Supporting Transaction Semantics

In mobile client-server database systems, caching of frequently accessed data is an important technique that will reduce the contention on the narrow bandwidth wireless channel. As the server in mobile environments may not have any information about the state of its clients' cache(stateless server), using broadcasting approach to transmit the updated data lists to numerous concurrent mobile clients is an attractive approach. In this paper, a caching policy is proposed to maintain cache consistency for mobile computers. The proposed protocol adopts asynchronous(non-periodic) broadcasting as the cache invalidation scheme, and supports transaction semantics in mobile environments. With the asynchronous broadcasting approach, the proposed protocol can improve the throughput by reducing the abortion of transactions with low communication costs. We study the performance of the protocol by means of simulation experiments.

Transactional client-server cache consistency

Client-server database systems based on a data shipping model can exploit client memory resources by caching copies of data items across transaction boundaries. Caching reduces the need to obtain data from servers or other sites on the network. In order to ensure that such caching does not result in the violation of transaction semantics, a transactional cache consistency maintenance algorithm is required. Many such algorithms have been proposed in the literature and, as all provide the same functionality, performance is a primary concern in choosing among them. In this article we present a taxonomy that describes the design space for transactional cache consistency maintenance algorithms and show how proposed algorithms relate to one another. We then investigate the performance of six of these algorithms, and use these results to examine the tradeoffs inherent in the design choices identified in the taxonomy. The results show that the interactions among dimensions of the design space impact performance in many ways, and that classifications of algorithms as simply “pessimistic” or “optimistic” do not accurately characterize the similarities and differences among the many possible cache consistency algorithms.

Highly concurrent cache consistency for indices in client-server database systems

In this paper, we present four approaches to providing highly concurrent B + -tree indices in the context of a data-shipping, client-server OODBMS architecture. The first performs all index operations at the server, while the other approaches support varying degrees of client caching and usage of index pages. We have implemented the four approaches, as well as the 2PL approach, in the context of the SHORE OODB system at Wisconsin, and we present experimental results from a performance study based on running SHORE on an IBM SP2 multicomputer. Our results emphasize the need for non-2PL approaches and demonstrate the tradeoffs between 2PL, no-caching, and the three caching alternatives.