I. INTRODUCTION
With the rising need for secure, reliable and accessible information in today’s technology environment, the need for distributed databases and client/server applications is also increasing. A distributed database is a single logical database that is spread physically across computers in multiple locations that are connected by data network links. Distributed database is a kind of virtual database whose component parts are physically stored in a number of distinct real databases at a number of distinct locations. The users at any location can access data at anywhere in the network as if the data were all stored at the user’s own location. The objective of a distributed database management system (DDBMS) is to control the management
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III. DISTRIBUTED DATABASE DESIGN
Distributed Database Systems are needed for the applications where data and its accesses are inherently distributed and to increase the availability during failures.
However, some additional factors have been considered for a Distributed Database:
A. Data Fragmentation: In Distributed Databases, we need to specify and understand the logical unit of Database Distribution and allocation. The database may be broken up into logical units called fragments which will be stored at various sites. The easiest logical units are the tables themselves. Two Types of Data Fragmentation are:
• Horizontal fragmentation: A horizontal fragment of a table is a subset of rows in it. So horizontal fragmentation spilts a table 'horizontally' by selecting the relevant rows and these fragments can be assigned to different sides in the distributed system • Vertical fragmentation: A vertical fragment of a table keeps only some attributes of it. It spilts a table vertically by columns. It is essential to include the primary key of the table in each vertical fragment so that the full table can bere constructed if
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Data Replication: A popular option for data distribution as well as for fault tolerance of a database is to store a separate copy of the database at each of two or more sites.A replicate of each fragment can be maintained at several sites. Data replication is the process of deciding which fragments will be replicated.
IV. FUNDAMENTALS OF TRANSACTION MANAGEMENT AND CONCURRENCY CONTROL
Transaction: A transaction consists of a series of operations performed on a database.
The major issue in transaction management is that if a database was in a consistent state prior to the initiation of a transaction, then the database should return to a consistent state after the transaction is completed.
Properties of Transaction: A Transaction has four properties that lead to the consistency and reliability of a distributed database. These are Atomicity, Consistency, Isolation, and Durability.
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Datatype Description smallint 1 byte is the minimum storage needed int Uses only the bytes that are needed. For example, if a value can be stored in 1 byte, storage will take only 1 byte bigint Uses only the bytes that are needed. For example, if a value can be stored in 1 byte, storage will take only 1 byte decimal This storage is exactly same as the vardecimal storage format datetime Uses the integer data representation by using two 4-byte integers. The integer value represents the number of days with base date of 1/1/1900. The first 2 bytes can represent up to the year 2079.
Hadoop [8] is an open source implementation of MapReduce programming model which runs in a distributed environment. Hadoop consists of two core components namely Hadoop Distributed File System (HDFS) and the MapReduce programming with the job management framework. HDFS and MapReduce both follow the master-slave architecture. A Hadoop program (client) submits a job to the MapReduce framework through the jobtracker which is running on the master node. The jobtracker assigns the tasks to the tasktrackers running on many slave nodes or on a cluster of machines.
Data is organised in two ways, firstly data is stored within the hash table i.e. in an array. Secondly it is stored in linked lists and the hash table is an array of pointers to such linked lists. Applications and some examples 1. Mid-Square -We square the identifier when calculating the hash function. 2.
Line 3: Which row from the table of highlighted data will the answer come from? In this example 2 rows in the table were highlighted. The first row is the list of Marks; the second row is the list of Grades. Therefore the answer will come from row 2. (REMEMBER – IGNORE THE ROW NUMBERS GIVEN IN THE WORKSHEET – ONLY LOOK AT THE TABLE OF GRADES TO FIND OUT WHICH ROW WILL GIVE YOU THE ANSWER)
Do we follow our documented procedures for backup and recovery? Note: IT backup is an important component of our BCP. For example, our BCP provides that that we do these things to minimise the risk of lost of electronic documents – some documents are scanned to tape, and softcopies are held by business units; remote replication; and disk
1. List and explain the top 5 factors that are required, at a bare minimum, to make an application secure. Security architecture, authentication, session management, access control, and input validation are the top five factors that make an application secure. Security architecture: OWASP verification requirements in security architecture verify all the application components and libraries that are present in the application are identified. A high level architecture of an application must be designed.
This component is when you transmit any file from one computer to another computer, this is usually a much larger file. Most of the webs users would explain this simply as sending it to another computer that is set up to receive it or to send it up onto the internet where several people will be able to access it from their own computers. For example, YouTubers upload their videos on to the YouTube
Information technology is more than just computers. Today, information technology must be conceived of broadly to encompass the information that businesses create and use as well as a wide spectrum of increasingly convergent and linked technologies that process the information. In addition to
Week 2: Aligning Risks, Threats, and Vulnerabilities to COBIT P09 Risk Management Controls Lab #2 Lab Report File: Risk Management – IS355 Sherry Best Nicole Goodyear January 23, 2018 Describe the primary goal of the COBIT v4.1 framework. Define COBIT. The purpose of COBIT is to provide management and business process owners with an information technology (IT) governance model that helps in delivering value from IT with understanding and managing the risks associated with IT. COBIT also bridges the gaps between control requirements, business risk, and technical issues.
Therefore, the database can be any type such as SQL, Not Only SQL (NOSQL), or other. Observation_4: The CSP needs to apply a virtualization technology on storage resources to serve CSUs’ demands efficiently. Therefore, a
Byzantine DBQ Essay Many people think of "devious" or "sneaky" when they hear the word Byzantine. Therefore, most tend to think it is not important to study the Byzantines. The Byzantines actually had a great impact on our lives today from the law system that we have in place to the architecture. There is more behind this loaded word than what meets the eye. The purpose of this essay is to explain why it is imperative to study the Byzantines.
A.1.b. Records and documentation. A.1.d. Support network involvement. A.2.a.
The author, Rick Riordan, keeps the story, The Hidden Oracle, interesting by using several literary devices to aid understanding. One technique the author using to keep the story interesting is using various literary devices to aid the reader’s understanding. First, the author aids the reader’s understanding by using imagery. For example, Apollo and Meg meet the queen ant. Apollo thinks, “Her majesty was three times the size of her largest soldiers-a towering mass of black chitin and barbed appendages, with diaphanous oval wings folded against her back.
Amazon is purely an online sales portal. Based on premium web rating organizations Amazon has a position ranging from 4 to 10 on a global ranking of premium websites. The presence of Amazon in the virtual world of internet is unquestionable. Big Data is a technology area which is highly talked about during the last several years. During the last 18 months, companies in the retail sector, manufacturing, construction, and technology areas have realized the extreme potential of Big Data and are trying to gain maximum advantage from it.
Relational Database Management System: This type of database management system that stores the data in the form of related tables. It is a social database administrator which deals with some typical kind of queries and uses SQL for the development of the database. This type of database is a very powerful database as it deals with the relations which makes the data manipulations easier other than any other database. It has the features of data entry, data deletion, and creating of new entry and records etc. the database provides the ease of accessing and maintaining data easily.