Distributed Databases

In: Computers and Technology

Submitted By mehakriaz
Words 2137
Pages 9
We take furniture company of Try Star international .It has two branches one in Lahore and other in Karachi. Old system were centralized and we design a new system of database which is distributed i.e. the database of the Lahore campus is in Lahore and the database of karachi campus is in Karachi i.e a collection of multiple ,logically interrelated databases distributed over a computer network.

A distributed database management system is defined as a software system that permits the management of the ddbs and makes the distribution transparent to the users.

Why we use distributed database?

In centralized system, all queries are handled by the main server and all loads are on the server but in distributed system, a separate server for each site exists. • In centralized system If centre goes down, everything is down. So you need to have offsite redundant servers. • In centralized system there is the single point of failure that can bring an entire company down in the event of a server crash but in distributed system if one server crashed down we get information from main server.

Distributed Database design:
The design of a distributed computer system involves making decisions on the placement of data and programs across the sites of the computer network .in the case of distributed DBMSs,the distribution of application invoves two things: • The distribution of the distributed DBMS softwares • the distribution of thr application of the programs that run on it
It has been suggested that the organization of the distributed systems can be investigated along three orthogonal dimensions: 1. Level of sharing 2. Behavior of access patterns 3. Level of knowledge on access pattern behavior

We find level of data sharing in our system and all the programs of our system are replicated at all the sites but data…...

Similar Documents

Distributed Database

...Today's business environment has an increasing need for distributed database and client/server applications as the desire for reliable, scalable and accessible information is steadily rising. Distributed database systems provide an improvement on communication and data processing due to its data distribution throughout different network sites. Not only is data access faster, but a single-point of failure is less likely to occur, and it provides local control of data for users. However, there is some complexity when attempting to manage and control distributed database systems. The DDBMS synchronizes all the data periodically, and in cases where multiple users must access the same data, ensures that updates and deletes performed on the data at one location will be automatically reflected in the data stored elsewhere. A distributed database can also be defined as a collection of multiple, logically interrelated databases distributed over a computer network. A distributed database management system is then defined as the software system that permits the management of the distributed databases and makes this distribution transparent to the users. Distributed database system is to referred as a combination of the distributed databases and the distributed DBMS Current trends in multi-tier client/server networks make DDBS an appropriated solution to provide access to and control over localized databases. Oracle, as a leading Database Management System (DBMS) vendor employs the......

Words: 3658 - Pages: 15

Distributed Database

...Assignment 8: Distributed Databases The reason for writing this paper is to clarify the importance of distributed database and why national chain restaurant should implement it. Given the situation presented in the assignment a small restaurant has grown to become a national restaurant chain and now they are concerning more on the distribution of data among different sites chains. For this approach distributed database architecture is suggested and reasons to implement the distributed database I will explain throughout the rest of this paper. The three reasons why an organization may have a need for distributed databases and best practices for implementation of distributed database would be that it provides the distributed transaction management. It provides the provision to do the distributed transactions like select, update and delete on the data without worrying about concurrency or locking problems and they distributed database are independent of given hardware. Today’s world involves a diversity of different machines like Sun machines, PCs, IBM machines, HP machines, and workstations of various kinds. In distributed DBMS all these machines are able to incorporate the data on all of those systems. The plan is to be able to run the same DBMS on a different hardware platform. Operating system independence distribute DBMS is independent of the underlying operating system like UNIX, Linux, Sun Solaris or Windows. All the databases in this model are compatible with......

Words: 944 - Pages: 4

Distributed System

...platforms. The database is the critical part of that platform. Therefore it is imperative that our cloud database be compatible with cloud computing. Key Design principles of the cloud model: The core design principle is dynamic scalability, or the ability to provision and decommission servers on demand. The shared-disk database architecture is ideally suited to cloud computing. It requires fewer and lower cost servers, it provides high availability, reduces maintenance costs by eliminating partitioning and it delivers dynamic scalability. Benefits of Cloud Computing: a. Lower Costs: All resources are shared resulting in reduced costs. b. Shifting CapEx to OpEx: This enables customer to focus on adding value in their areas of competence. It allows customer to focus their money and resources on innovating. c. Agility d. Dynamic Scalability: It can smoothly and efficiently scale to the spikes with a more cost-effective pay-as-you-go model. e. Simplified maintenance: All Patches and upgrades are deployed across the shared infrastructure. f. Large scale prototyping/load testing g. Diverse platform support h. Faster Management approval i. Faster development With corporate adoption of cloud computing there are explosion of cloud options. One of those options is the provisioning of database services in the form of cloud databases or Database-as-a-Service (DaaS). The Cloud databases serviced......

Words: 3040 - Pages: 13

Distributed Database

...Distributed database is one in which multiple database sites are linked by a communications system in such a way that the data at any site is available to users at other sites. Depending on the needs of an organization the following reasons would be why they would have the needs of distributed databases: * Improved reliability. A distributed system is more reliable than a centralized one, because processing is done at several sites, so failure of a single node does not halt the entire system. Distributed systems can be designed to continue to function despite failure of a node or of a communications link. * Better Data availability. Distributed database systems often provide for replication of data. If a node fails, or the only link to a node is down, its data is still available, provided a copy is kept somewhere else in the system. * Lower communication cost. If data used locally is stored locally, communications cost will be lower, since the network will not be used for most request. In centralized system, the communications network is needed for all remote requests. However, we must consider the additional cost for the database software, additional storage costs for multiple copies of data items and software, higher hardware costs, and higher operating costs the distribution can entail. Distributed database has different types of distributed systems. These systems ate homogeneous and heterogeneous. With homogeneous all modes use the same hardware and......

Words: 866 - Pages: 4


...tools, used operating system, database management system and its mechanism in respect of Client/Server computing and network components used in order to build effective Client/Server applications. vi Preface Last but not the least, this work is primarily a joint work with a number of fellow teacher who have worked with us. My parents, wife Meera, and our children, Akanksha and Harsh. I am particularly grateful to Dr. A. P. Singh, Principal, Udai Pratap Inter College, Varanasi; Dr. D. S. Yadav, Sr. Lecturer, Department of Computer Science and Engineering, IET, Lucknow; Dr. A. K. Naiyak, Director IIBM, Patna, former President of IT and Computer Science Section of Indian Science Congress Association; Prof. A. K. Agrawal, Professor and Ex-Head of Department, Computer Science and Engineering IT, BHU, Varanasi and Mr. Manish Kumar Singh, Sr. Lecturer, Rajarshi School of Management and Technology for providing the necessary help to finish this work. Suggestions and comments about the book are most welcome and can be sent by e-mail to scy@rediffmail.com. Subhash Chandra Yadav Contents Preface v 1–23 1 2 4 4 5 7 7 8 9 9 9 12 15 16 17 17 17 18 19 19 21 22 23 1 INTRODUCTION 1.1 What is Client/Server Computing? 1.1.1 A Server for Every Client 1.1.2 Client/Server: Fat or Thin 1.1.3 Client/Server: Stateless or Stateful 1.1.4 Servers and Mainframes 1.1.5 Client/Server Functions 1.1.6 Client/Server Topologies 1.1.7 Integration with Distributed Computing 1.1.8......

Words: 79055 - Pages: 317

Distributed Transaction

...A Distributed Transaction Management Scheme for Multidatabase Systems* Xinfeng Ye, Department of Computer Science, University of Auckland, New Zealand. Abstract finsaction management in a multidatabase sys- tem must ensure global serializability. Local seri- alizable execution is, by itself, not suficient to en- sum global serializability, since local serialisation or- ders of subtmnsactions of global transactions must be the same at all systems. In this paper a distributed tmnsaction management scheme is introduced. The scheme maintains autonomy of the local database systems. It is free from global deadlock, and, guar- antees fairness in the execution of the tmnsactions in the system. 1 Introduction A multidatabase system (MDBS) is a collection of pre-existing autonomous, and possibly heteroge- neous, local database systems (LDBSs). Transac- tions in an MDBS are of two types: Local transactions: Those transactions that only access data m,anaged by a single LDBS. Global transactions: Those transactions that ac- cess data managed by more than one LDBS. Transaction management in the MDBS is hierar- chical. Each LDBS controls the local transactions and the subtransactions of the global transactions at its site, and assures serializable execution at that site. The MDBS software controls the global trans- actions, and assures global serializability. Global serializability guarantees the correct con- current......

Words: 4732 - Pages: 19

Normally Distributed

...Question 1. The graduate selection committee wants to select the top 10% of applicants. On a standardized test with a mean of 500 and a standard deviation of 100. What would be the cutoff score for selecting the 10% of applicants, assuming that the standardized test is normally distributed? Mean = 500; deviation = 100; x = 10% (100-10)/100=.90 (looking at the normal distribution curve, the closest I could get was .8997 which rounds up to 0.90) and the Z score is 1.28. 1.28*100 = 128 and the mean is 500 so I will add it to the 128 (128+500=628). So the cutoff point would be 628. Question2 The average commute time via train from the Chicago O’Hare Airport to downtown is 60 minutes with a standard deviation of 15 minutes. Assume that the commute times are normally distributed. What proportion of commutes would be: a. Longer than 80 minutes (80-60)/15 = 1.333 (z > 1.333) 1.33 = .092 (9.2%) b. Less than 50 minutes (50-60)/15 = -.667 (z< -.667) -.667 = .251 (25.1%) c. Between 45 and 75 minutes (45-60)/15 = -1.000 -1.00 = .1587 = .159 (75-60)/15 = 1.000 1.000= .8413 = .841 .841 - .159 = 0.682*100 = 68.2% Question 3 Bob takes an online IQ test and finds that his IQ according to the test is 134. Assuming that the mean IQ is 100, the standard deviation is 15 and the distribution of IQ scores is normal, what proportion of the population would score higher than Bob? Lower than Bob? (134 – 100)/15 = z 34/15 = 2.2666 Z =......

Words: 328 - Pages: 2

Distributed Systems

...Distributed Systems: Concepts and Design Edition 3 By George Coulouris, Jean Dollimore and Tim Kindberg Addison-Wesley, ©Pearson Education 2001 Chapter 1 1.1 Exercise Solutions Give five types of hardware resource and five types of data or software resource that can usefully be shared. Give examples of their sharing as it occurs in distributed systems. 1.1 Ans. Hardware: CPU: compute server (executes processor-intensive applications for clients), remote object server (executes methods on behalf of clients), worm program (shares cpu capacity of desktop machine with the local user). Most other servers, such as file servers, do some computation for their clients, hence their cpu is a shared resource. memory: cache server (holds recently-accessed web pages in its RAM, for faster access by other local computers) disk: file server, virtual disk server (see Chapter 8), video on demand server (see Chapter 15). screen: Network window systems, such as X-11, allow processes in remote computers to update the content of windows. printer: networked printers accept print jobs from many computers. managing them with a queuing system. network capacity: packet transmission enables many simultaneous communication channels (streams of data) to be transmitted on the same circuits. Data/software: web page: web servers enable multiple clients to share read-only page content (usually stored in a file, but sometimes generated on-the-fly). file: file servers enable multiple clients to......

Words: 38975 - Pages: 156


...media Share (video, musik, gambar) antara perangkat yang berbeda, akses kontrol antar perangkat (devices), dan dapat berbagi media di banyak perangkat, seperti: PC, TV, ponsel, tablet dan kamera digital yang mampu mendukung AllShare Services. Konvergensi / Convergence / MultiScreen Convergence merupakan framework yang dapat membantu komunikasi dua arah antara TV dan perangkat lainnya (smartphone, tablet, dll). Convergence memungkinkan perangkat terhubung ke jaringan dan mencari device lainnya menggunakan UPnP dan berkomunikasi melalui HTTP protokol menggunakan REST API. SSO (Single Sign-On) Single Sign-On merupakan mekanisme untuk mengelola informasi account pengguna untuk aplikasi Smart TV. Informasi account dienkripsi disimpan dalam database dan tersedia untuk aplikasi masing-masing. Berkat ini, pengguna tidak harus berulang kali memasukkan informasi pribadi. IME (Input Method Editor) IME (Input Method Editor) adalah modul umum yang memungkinkan input teks dalam aplikasi. Pengguna Smart TV dapat memasukkan teks dengan menggunakan remote control. IME menampilkan keyboard virtual pada layar (qwerty atau gaya ponsel) dan pemetaan tampilan karakter yang sesuai untuk input remote contoller. 5. Mulai Membuat Aplikasi Smart TV Pada modul ini, akan dibahas bagaimana membuat aplikasi pada Samsung Smart TV. Pada bagian pertama akan diperlihatkan bagaimana kita membuat aplikasi berita menggunakan beberapa resource dari website tertentu. Beberapa hal yang dibutuhkan dalam......

Words: 1183 - Pages: 5

Design and Applied Research of the Distributed Real-Time Database in Smart Grid

...Design and Applied Research of the Distributed Real-time Database in Smart Grid Chunfeng Liu, Yan Jiang, Feng Zhao, Qiao Sun, Yang Zhang, Zhiqi Li, Chao Li Beijing Guodiantong Network Technology Company Ltd., No.1 Hangfeng Road, Fengtai District, Beijing, 100070, China {liuchunfeng, jiangyan, feng_zhao, sunqiao, zhangyang2, lizhiqi, lichao3}@sgepri.sgcc.com.cn database. Both timing constraints and data consistency should be taken into consider in real-time database systems when scheduling the transactions so that they can be accomplished by their corresponding deadlines[3]. For instance, both the query and update on the acquisition data of smart electricity meters, mainly working for the calculation of the multistep electricity price and electricity increment, must satisfy not only the database consistency constraints but also the time constrain, processed within the given deadlines. Apart from the time constraints that are out of the demand of continuously data tracking, timing correctness requirements are also proposed due to the need to keep data available for the decision-making activities of the controlling systems[4]. Based on these situations, real-time databases are used in a wide Keywords— Distributed, real-time database, smart grid, typical range of applications in the power industry. applications, electric energy data acquire system At the same time, the electricity data also has astounding I. INTRODUCTION quantities. In China, the scale of the data points in......

Words: 4176 - Pages: 17

Distributed Systems

...Server Training (16 Courses) Training on how to build and manage SQL Server databases. Our SQL Server Training Courses provide the skills needed to build a solid foundation for SQL Server development. Introduction An overview of DBMS technology * How data is accessed, organized and stored * The database development process * Query and application development tools * CASE tools for database analysis and design * Tables, attributes and relationships * Primary and foreign keys * Relational integrity constraints * Manipulating data: selection, projection, join, union, intersection, difference * An integrated, active data dictionary * The query optimizer * Developing the logical data model * Mapping the data model to the relational model * Specifying integrity constraints * Defining the data in the data dictionary * Capturing entities, attributes and identifiers * Describing relationships: one-to-one, one-to-many, many-to-many * Optional and mandatory relationships * Resolving many-to-many relationships for implementation * Generating the SQL to build the database * Reverse engineering to capture the design of an existing database * SQL Programming Language Introduction 1 Days * Write SQL code based on ANSI/ISO standards to build Microsoft SQL Server or Oracle database structures * Update database content with SQL and transaction handling * Retrieve data with filter conditions and......

Words: 1010 - Pages: 5

Distributed Databases

...Assignment 8: Distributed Databases Due Week 9 and worth 50 points A few years have passed, and the restaurant has grown to become a national restaurant chain. Now, they are concerned that remote and branch offices and restaurants in all fifty states will not have ready access to the data. Your supervisor has asked you to write a report to address the concerns of the customer and figure out how to expand the single server / single location database so the other 500 locations will be able to access and update the system. Write a 2-3 page paper in which you: 1.List three (3) reasons why an organization may have a need for distributed databases and best practices for implementation of distributed database. 2.List and explain: ◦The software and hardware components of a distributed database. ◦Techniques for distributed data placement. ◦Strategies for distributed query processing. 3.Briefly explain how an organization would allow programmatic access to a database through the Internet. 4.Please make any or all appropriate assumptions to answer the following. ◦Propose a solution for the national restaurant chain on a distributed database system that will work for them. ◦Create a diagram using Visio, Microsoft Paint, or other graphical creation utility of your choosing to illustrate the diagrams supporting your conclusion. Note: The graphically depicted solution is not included in the required page length. 5.Use at least three (3) quality resources in this assignment.......

Words: 440 - Pages: 2


...COURSE OUTLINE DATABASE SYSTEMS: DIS 308 INTRODUCTION Databases are part of our day to day lives. When we are registering as students, we are interacting with databases, when we go to the bank, pay our electricity bills or pay water bills our accounts are on a database, even when we are browsing the net; information is coming from several databases. Therefore, databases are sources of information kept on electronic storage media for easy retrieval by interested parties. OBJECTIVE The objective of this unit is to introduce students to the concepts, architecture and design methods of database systems. At the end of the course you will be expected to translate logical models into physical databases LECTURE ONE: Introduction to Databases * Database Terminologies * Tradition Files * Database Management Systems (DBMSs) * Characteristics of Database Approach * Database Users * Database Storage LECTURE TWO: Database Systems Concepts and Architecture * Data Models * Three Schema Architecture * Database Languages and Interfaces LECTURE THREE: Database System Environment * Types of Databases * Database System Utilities * Tools Environment and Communication Facilities * Centralized and Client Server architecture for DBMSs * Distributed Databases * Data Warehouse LECTURE FOUR: Database Design Process * Logical Database Design Process * Physical Database Design * Object-Oriented Database Design LECTURE FIVE: CAT LECTURE SIX: ......

Words: 252 - Pages: 2


...4600-01 INTRO TO DATABASES CLOUD DATABASES SUBMITTED BY: ALICIA RUCKER INSTRUCTOR: DR. LUIS VIDAL SPRING 2016 Abstract A cloud database is a database that typically runs on a cloud computing platform. Users can run databases on the cloud independently, using a virtual machine image, or they can purchase access to a database service, maintained by a cloud database provider. There is a proposed 5 layer cloud architecture. The External Layer, which is the first, is closest to the user. The second layer is the Conceptual Middleware Layer. The third layer is the Conceptual Layer. In this layer programming techniques, transaction management, query processing and optimization are considered. The fourth layer is the Physical Middleware Layer, where interoperability between various platforms is considered. Last, there is the Physical Layer which is concerned with how data is stored and accessibility. A cloud database management system is a distributed database that delivers computing as a service instead of a product. It is the sharing of resources, software, and information between multiply devices over a network which is mostly the internet. An example of this is Software as a Service or SaaS. SaaS is an application that is delivered through the browser to customers. A database management system is a software package with computer programs that control the creation, maintenance, and use of a database. It allows organizations to conveniently develop databases for......

Words: 851 - Pages: 4


...Examples of database and table creation The following examples use the create keyword to create the sample staff database and define the tables. These example OQL statements illustrate the use of the column constraints and the default keyword. Example 1 create database staff; // creates the staff database The following insert defines the managers table. create table staff.managers ( EmployeeID int NOT NULL PRIMARY KEY, Name text NOT NULL, Department text default "Sales", Gender text, Age int, unique ( EmployeeID ) // indicates that the data in the // EmployeeID column must be unique. ); For the managers table: • The EmployeeID and Name columns cannot be NULL. • The EmployeeID column is the primary key and must be unique. • If no value is inserted into the Department column for a given record it takes the value "Sales". Example 2 The following insert creates the staff.employees table. create table staff.employees ( EmployeeID int NOT NULL PRIMARY KEY, Name text NOT NULL, Skills list type text, Gender text, Age int // There is no comma here because this ...

Words: 978 - Pages: 4