What Is Rdbms Ordbms And Oodbms Information Technology Essay

What Is Rdbms Ordbms And Oodbms Information Technology Essay A set of computer programs which controls the formation, preservation, and the use of database with computer as a platform is called a database management system (DBMS). The control of organization-wide database development in the hands of database administrators (DBAs) is permitted by the database management system. It helps the use of integrated collection of data and files and also easily permits the access of the same database to different user application programs. The database models like network model or relational model can be used by the DBMS. Another feature of the DBMS is allows users and other software to store and get back data in a structured way in large systems. The users can write simple question in query language to retrieve information instead of writing computer programs. Fourth-generation programming language (4GLs) and other application development features provided by DBMS are very helpful to specify the logical organization for database and access and use the information within a database. Relational Data Base Management System (RDBMS) The abbreviation form of Relational Data Base Management System is RDBMS. The structure of RDBMS is database tables, fields and records. Each RDBMS table consists of database table rows and each database table row consists of one or more database table fields. RDBMS is used by main frame, midrange and microcomputers. MS SQL Server, DB2, Oracle and MySQL are the most popular RDBMS. The data are stored in the form of tables which might be related by common fields. The data stored in the database table are manipulated by the rational operators given by RDBMS. SQL is the database query language in most RDBMS. Why RDBMS? We will use the terms tables and relations interchangeably. In a RDBMS, the data is logically perceived as tables. _ Tables are in logical data structures that we assume hold the data that the database intends to represents _ And tables are not physical structures. _ Each table have a unique table name There are advantages and as well as disadvantages in the RDBMS. The advantages of RDBMS are Fast and easy to pop out data as relation among entities is well defined More secure and normalization Problems are avoided when two things are processed at the same time data can be managed in proper manner Accuracy The disadvantages on the other hand are A professional is needed to deal with Proper training is required Need software and hard ware The model is not easy to the end user to run quires Object Relational Database Management System (ORDBMS) The object relational database management system is known as a database management system which is alike to a relational database, but with an object oriented database model. This system supports classes, objects and inheritance directly in database schemas and in the query language. Besides, extension of the data model with custom data type and methods are supported by ORDBMS. The well-organized management from a limited set of data types is focused in traditional RDBMS but object relational DBMS on the other hand permits web sites development experts to join their own data types and methods. Advantages of ORDBMS: Large storage capacity is ensured in Object Relational Database Management Systems which benefits for the web based development. Reasonably quick access speed Massive scalability of ORDBMS is beneficial. Outstanding manipulation power of object databases is boasted in ORDBMS APIs and server subsystems are added to support object functionality. The database engine is completely redesigned A new object-oriented layer is added to support rich data types Disadvantages of ORDBMS ORDMBS fails in High speed internet applications. The IDC opines that the ORDBMS market has the possibility to exceed the size of ODBMS in the next two years time in web based development Object Oriented Database Management system (OODBMS) Object Oriented Database Management system is the most excellent alternative to resolve impedance mismatch causing in the use of Relational Database Management System as objects have to be mapped to table. Database management is combined with object oriented programming concepts by the object oriented database management system. The principles of database management such as isolation, durability, consistency and atomicity and the object oriented programming concepts consist of of inheritance, encapsulation and polymorphism. The mixture of these ideas permits easiness in the management of large number of data, results in system reliability and guarantees support for query languages. Therefore, from the description given above it can be concluded that an OODBMS is not only a database management system but also a complete object oriented development setting. Software development companies use OODBMS as an alternative because it follows intelligibility while objects are accessed in the database. The Main objective of the OODBMS is to give consistent, data independent, secure, controlled and extensible data management services to support the object-oriented model. They were created to handle big and complex data that relational databases could not. The most main characteristic is the joining of object-oriented programming with database technology, which provides an integrated application development system. Object-oriented programming results in 4 main characteristics: inheritances, data encapsulation, object identity, and polymorphism. Object Identity, Object Structure, and Type Constructors Object Identity An OO database system provides a unique identity to each independent object stored in the database. This unique identity is typically implemented via a unique, system-generated object identifier (OID). The OID cab is assigned to program variables of the appropriate type when needed. The main property required of an OID is that it be immutable; that is, the OID value of a particular object should not change. This preserves the identity of the real-world object being represented. Merits of OODBMS over RDBMS The impedance mismatch is completely cancelled out in OODBMS and on the other hand in a relational database system a problem is always faced by a custom software development company. There was lot of wastage of time in RDBMS while objects had to be mapped with tables and the table mapped with objects. In the RDBMS, problems have to be faced by the users when identifying the records and they have to make sure that no two records have the same primary key. In the OODBMS this problem is completely avoided by its unique OIDs. OODBMS can deal with complex data than RDBMS as in ODBMS, a large class able to hold lot of intermediate sized classes, which can keep even more medium sized classes. The database management system maintains the connection between objects and the constraints on objects in an object oriented database, which means, the objects themselves. They permit support of complex application which is not supported by the other models. The programmability and performance, improve navigational access, and simplify concurrency control are improved by the object oriented database. The risks linked with the referential integrity are reduced in OODBMS and it gives an enhanced user metaphor than the relational model. Object oriented database can store both complex component and large structure. The large objects in object oriented database do not need to be broken apart and reassemble by application. Therefore object oriented data base do not suffer performance degradation. RDBMS does not allow the nested structure. These category of applications widely found in CAD/CAE, aerospace, etc. But these applications are easily supported in OODBMS. Besides, it is better to deal with the complex structure in the form of objects rather than table, tuples and records in RDBMS. Limited numbers of data types such as integer and string and limited number of built in operations are available in the relational database management system. This database management system is suitable for simple and few number of data types. The OODBMS on the other hand are appropriate for application where the relationships among elements in the database carry the key information. Conclusion According to the report we can takes some con-clusions regarding RDBMS and OODBMS: †¢ Relational databases have as their objective to ensure data independence ie> Normalized data is separated from processing and the processing corresponding to satisfy-ing informational requirements need not be totally pre-defined, thus accepting ad-hoc re-quirements too. †¢ Object oriented databases have as their main objective encapsulation, being stored together with the data and the methods. They are inseparable. It is said that we have to do with an independence of classes and not with an independence of data. †¢ An OODBMS and not an RDBMS is needed while in the reference applications we have to do with complex data. †¢ The object oriented database mar-kets will continue to develop, but they will still (represent) only a fraction of the traditional databases. †¢ It is appreciated that RDMSs hold the largest part of the largest part of the data-bases. But the prospect is that they will still co-exist for a long time future with the OODBS. ORDBMS complicates database design due to its new richness. There are more alternative designs that can be used to represent a particular situation, and it is not always obvious which to pick. Unthinkingly applying some of these features, such as the COLLECTION columns, create problems.

Become a Better Driver

In every major city accidents happen in which people are injured or killed. These unintended injurious events are caused by a â€Å"mistake† made by the parties involved (Hughes). Many people are good drivers, but it would be good for people to learn to be better drivers. It will help people if they have to retake their license test when they renew their license. This will help them follow the road rules, be more respectful to other drivers, and avoid other distractions while driving. If people follow the road rules, they will learn to become better drivers. There are many different rules that drivers have to learn in order to get their license. If they follow the same rules they learned in the beginning, then there shouldn’t be as many wrecks today as there are. If everyone has to retake their license test when their license expires, then that will help them remember the road rules. An article states, â€Å"U-turns account for over 19 deaths and 654 serious crashes between the year 2004 and 2008† (Road Safety). Recently there have been some changes in the road rules because there have been so many wrecks. In, â€Å"Five Thousand Teenagers Die Annually in Crashes† it states, â€Å"In 2004, more than 2,500 teens were in fatal crashes because of failing to yield or veering out of their lanes† (Hughes). Mistakes like this cause a lot more crashes. So it is important the people retake the license test so they learn to become better drivers so not so many accidents happen. Drivers should learn to be more respectful toward other drivers. When driving, people don’t pay attention to other drivers. Such as at four way stops you need to make sure you wait until it’s your turn to go. Don’t just go because you don’t feel like waiting. â€Å"Intentionality can be seen in a range, from deliberate carelessness (hope no one gets hurt) to recklessness (too bad for them if they don’t get out of the way)† (Hughes). When drivers don’t care about other drivers on the road, more than likely, there are going to be accidents. An article states, â€Å"Weekly, there are stories reported of â€Å"accidents† that are really events based on bad decisions, which have predictable results† (Hughes). Drivers pay too much attention to other distractions. There are cell phones, radios, GPS’s, billboards, etc. A lot of drivers have wrecks because the distractions cause them to pay attention to something else other than driving. Devices aren’t the only distractions. When teenagers have friends in the car with them it is also a distraction. When teenagers drive with their friends, it causes them to not pay as much attention to the road as they should. â€Å"44% of teens acknowledge they drive more safely without friends in the car† (Hughes). Drivers need to pay attention to the road and other drivers instead of everything else going on. Many people consider themselves good drivers. There are always ways that someone can become a better driver, even if you think you already are. In an article it states, â€Å"In the United States, an average of 5,000 teens die every year in car crashes- an average of 14 teenage lives lost every day† (Hughes). If everyone was as good of a driver as they think they are then that many teens would not die yearly. That is why everyone should have to retake their license test when they have to renew their license. Sometimes accidents can just happen regardless of how good of a driver the person is. There is really no way of stopping these kinds of accidents except for trying to avoid them in all possible ways. But even if you try to avoid them, the accident might still happen. If drivers have to retake their license test it would help them keep aware of their surroundings and how to avoid accidents. Everyone can learn to be a better driver by following the rules of the road, respecting other drivers, and by not getting distracted by other things. Although almost everyone says they are good drivers there is always room for improvement. Become a better driver so there will be fewer accidents yearly.

Hazards in Dhaka City Essay

During the last couple of decades Dhaka city is one of the fastest growing metropolises in the world. The urban development seems to lack in planning and the problem of urbanization are intensified by high population growth and rural urban migration. Again, Bangladesh suffers from natural calamities every now and then and the urbanization of metropolitan Dhaka is also affected by it. The existing utility services are not capable of coping with the increased demand of the urbanization process. Faulty planning, Lack of coordination among various agencies and overall disregard to environment issues affecting Dhaka include floods, which are associated with river water overflow and rain water stagnation, earthquakes and tornadoes. Flood Hazard: Flood is a type of hydro-meteorological phenomenon and it is very hazardous as it can cause devastating losses in property and human lives. Fast and unplanned development aggravates the consequences of flooding by increasing the monetary costs of losses. These kinds of losses are especially high in urban areas which would be possible to ease with proper planning and management of the urban structures. Geographical Information Systems (GIS) based modeling and Remote Sensing (RS) techniques can help by supplying maps and techniques as assistance to make early warning for risk areas. In this case study, different criteria have been analyzed that have potential impact on the amount of devastation, such as the elevation of the areas, flooding depth, building density, terrain slope, soil type, land use types etc. Based on different factors analysis, results are visualized with the help of GIS and RS presentation and dissemination techniques. In addition, the impacts of different factors on flooding itself are also discussed. Finally, a flood prediction map for Dhaka City Corporation (DCC) in Bangladesh was prepared using the Multi-Criteria Evaluation (MCE) method with particular focus on the different criteria that influence the flooding in Dhaka city. Water Logging: Water logging is a very common problem in Dhaka city during the monsoon period as well as all the year round. Even a little rain causes serious  problems in some parts of the city on every occasion and can create water logging situation for several days which in turn causes huge infrastructural damages by reducing the amount of accessible assets and supplies in the city. This situation normally occurs due to unplanned infrastructure development, insufficient or limited drainage systems, blockage of the drainages, lack of consciousness of these problems by the inhabitants, unplanned build-up of areas within the city, filling up the canals, lakes and water bodies in areas which are mainly acquired by housing companies and brick burning industries within the city. The Dhaka city is usually flooded as a result of rainfalls and the high water level of surrounding river systems. For instance, 1998 flooding was the most catastrophic in the flooding history of Bangladesh, where Dhaka city was affected by heavy rainfall and the high water levels of the river system. Unplanned urbanization is increasing water logging. Earthquakes: The city can be severely affected by earthquakes as it has already happened in the past. Intensities of VI, VII, and VIII have already been registered in the city. The national building code of Bangladesh (BNBC 1993) includes three seismic zones, and Dhaka is located on the second one with a zoning coefficient equivalent to the 15% of the gravity (z=0.15g). According to the results of the Earthquake Disaster Risk Index (EDRI) project, major earthquake risk is associated with the high vulnerability of the building stock due to both poor materials and poor construction processes. Tornados: The two transitional periods between southwest and northeast monsoons over the Indian sub-continent are characterized by local severe storms. The transitional periods are usually referred to as pre-monsoon (March-May), and post-monsoon (October- November). It is the pre-monsoon period when most of the abnormal rainfall or drought conditions frequently occur in different parts of Bangladesh. Also there are severe local seasonal storms, popularly known as nor?westers (kalbaishakhi). Severe nor?westers are generally  associated with tornadoes. Tornadoes are embedded within a mother thundercloud, and moves along the direction of the squall of the mother storm. The frequency of devastating nor?westers usually reaches the maximum in April, while a few occur in May, and the minimum in March. Nor?westers and tornadoes are more frequent in the afternoon. Table 3 shows some of the devastating nor?westers and tornadoes that hit Bangladesh. Nor?westers may occur in late February due to early withdrawal of winter from Bangladesh, Bihar, West Bengal, Assam, and adjoining areas. The occasional occurrence of nor?westers in early June is due to the delay in the onset of the southwest monsoon over the region (Karmakar, 1989). Table: Some of the devastating westers and tornadoes

Korea threats essays

Korea threats essays The article that I found deals with one of the countrys that President Bush has deemed the axis of evil. North Korea is one of a few counties that pose as a genuine threat, not only to the United States, but to the rest of the world as well. North Korea has finally admitted to an active nuke program after it has promised to discontinue their activity. Their nuclear capability worries the people of South Korea and the United States, which has been expressed numerous times by President Bush. North Korea is the country that poses as a serious threat to the United States. Iraq is the other country that Bush has labeled was part of the axis of evil; Iran is the only other country than North Korea that is seen as a large threat. The United Sates had arranged to help North Korea in 2002; in fact they were ready to take economic and political steps to improve the lives of North Korea civilization. North Korea then admitted they had a mass destruction program; this is after the US rightfully vowed not to harbor any country that supports terrorism. North Korea has continually let the international community that they have the ability to build nuclear warheads since 2002. At the end of 2002, they were found two have enough plutonium two build two nuclear bombs. They were trying to lure the United States to help North Korea in their never ending war with South Korea. North Korea wanted the US to look out for their people and give food to a malnourished country. At the same time they were trying to get our support by threatening our country. In conclusion, according to the just war theory the country that we would have rightfully gone to war with is North Korea. The just cause is seen as to secure the life of not only the people in North and South Korea but also all the countries that are in danger by North Korea. Iraq was never found to have mass weapons of destruction, and that is the main reason people are ex...

Introduce Kids to Weather with These Coloring Pages

Introduce Kids to Weather with These Coloring Pages One of the earliest ways kids begin learning about the weather is by drawing and coloring weather symbols like suns, clouds, snowflakes, and the seasons. Teaching children about the weather with art and pictures not only makes it easier for them to understand, it also makes learning about severe and more serious kinds of weather less scary. Weve rounded up a collection of  family-friendly  weather coloring books offered by  the National Weather Service that help keep families informed and safe during severe weather events. Kids are encouraged to read about each severe storm type and then color in the pictures.   Meet Billy Maria Created by NOAAs National Severe Storms Laboratory,  Billy and Maria are two young friends who learn about severe weather through their adventures in  thunderstorms, tornadoes, and winter storms. Young students can accompany them by reading each story page and then coloring in the pictures.   Best for ages: 3 to 5 years The smaller coloring spaces, large text, and  simple sentences make these books appropriate for younger children.  Ã‚   Severe Weather with Owlie Skywarn NOAA also aims to capture the attention of kids with Owlie Skywarn, their official weather mascot.  Owlie is known for being wise about the weather and can help your children and students to do the same.  Booklets are 5-10 pages long and include fact boxes with illustrations that can be colored in. A  quiz (true/false, fill in the blank) is included at the end of every book to test what kids have learned.  Ã‚   In addition to the Owlie Skywarn coloring books, kids can also follow Owlies weather adventures  on Twitter (NWSOwlieSkywarn) and Facebook (nwsowlie). Some of Owlies Activity books  talk about: TornadoesHurricanesFloodsLightningWinter Storms Best for ages:  8 and up The coloring books are expertly designed and very informative, but almost too informative. The font type is quite  small and the information is a little above the coloring book stage of student interest.   Teachers: Weave Coloring Into Your Weather Science Lesson Plans Teachers can  implement these weather coloring books into the classroom as part of a daily plan over the course of five days. Using a severe storms theme, we suggest teachers present all of the materials one day at a time. Print out all of the booklets in the list, but don’t pass out the quiz. Present the material to students and then give them the quiz to take home and complete with their families. Tell students their assignment is to â€Å"teach† their families about severe storm preparation. Parents: Make Weather Coloring An Anytime Activity Just because these coloring books are educational, doesnt mean they dont make a good anytime coloring activity! Parents and guardians should use them at home, too, to begin to teach kids about weather safety from  a very young age.  Each of the coloring books actually shows kids how to react in the event of severe weather so that whenever storms do hit home, your kids will feel more  relaxed and ready for them.   Follow this family plan to implement these booklets in your family nights. We suggest parents plan one night per week to review the written information in the booklets. Since there are five booklets, you can complete this small course of study in just five weeks. Since storm preparation is so vital, you have to remember to practice the safety information over and over. Here are the steps: Assign one night for reading and reviewing the information together.Give your kids supplies to color the pages. Make sure you tell your kids to think about the safety information as they color.Check with your kids periodically to see what they remember. Put the details into practice at  home with random questions about the material. Since storms can happen suddenly, knowing what to do quickly and â€Å"on the spot† is vital to learning and preparation.At the end of the week, go over the information together again. Present the Owlie Skywarn quiz and see how many of the answers your kids can guess.Design a weather drill poster or paper so that you and the rest of your family will know what to do during a storm. Post it to a central spot, like the refrigerator.  Periodically, practice the weather drills so that your family stays refreshed.

Organisational Design Problem Coursework Example | Topics and Well Written Essays - 2000 words

Organisational Design Problem - Coursework Example The internal structures did not change to match the growth of the company like required for successful global expansions. As observed, the corporate culture left loopholes where the inferior performers get rewarded while the productive employees get penalized. The core value of the organizational structure is to ensure that activities like task allocation, coordination, and supervision get stirred towards achieving goals of an organization. As such, the structure of an organization is critical to the performance and operational modes. The structure is known to affect an organization in two positive dimensions. The first dimension is that it offers a foundation for the development of standard operating procedures and routines. The second dimension is the determination that individuals handle a certain task and decision-making process. The structure ensures that it defines the extent with which these views shape the organization’s choice (Campbell and Craig, 2005). There are several challenges faced by the company due to rapid expansion and poor organizational structure. When an organizational structure does not coincide with facts evolving in operational action, it leads to poor performance when the company is expanding (Armstrong, 1996). COY’s inadequate organizational structure hampered cooperation regarding the established centers and the headquarters. Consequently, it leads to the hindrance of completion of defined operations (Peris-Ortiz and Sahut, n.d.). The structure results in a lag in time and misuse of resources when poorly implemented. As such, the organizational structure should be adaptive to the process requirements. The primary aim would involve optimizing the ratio of effort and input to output (Bahram Ranjbarian, 2011). Normally, the strategy of a company that has poorly implemented its organizational structure will change but the

Analysis of the business situation of the Virgin Mobile Essay

Analysis of the business situation of the Virgin Mobile - Essay Example bile operates as a virtual network operator, riding on the physical network of T-Mobile, and later Everything Everywhere (Answers Corporation, 2014; Virgin Mobile USA, 2009; Telecompaper, 2014; RCRWirelessAdmin, 2011; RCRWirelessAdmin, 2013; Thomas, 2013; Ofcom, 2013). Virgin Media UK provides a breakdown of financial data for Virgin Mobile in its UK investor relations reports of financial performance. That aside one can get a glimpse of the kinds of numbers that Virgin Mobile is able to generate too, by looking at the financial and subscriber data for Virgin Media, which is the owner of Virgin Mobile in the UK. As of end of December of 2013, Virgin Mobile had about three million customers, a third of whom are prepaid customers, while more than two million are postpaid customers. They offer voice and data services to this customer base, as well as content. The direction of growth is towards increasing the base of postpaid customers (Virgin Media, 2013; Virgin Media, 2014). Moving on to the financial numbers, total revenues for 2013 amounted to 1.846 billion pounds, a substantial slowdown from revenues of over 3 billion pounds for 2011 and for 2012. As a group, this slowdown reflects a general drop in total revenues for the Virgin Media Group, from about 4 billion pounds for 2011 and for 2012, to just 2.3 billion pounds for 2013. The large drop can be attributed to the large drop in revenues for Virgin Mobile (Virgin Media, 2013; Virgin Media, 2014; Google, 2014b). The chosen SBU unit for analysis in this paper is Virgin Mobile n the UK, as a subsidiary of Virgin Media. In turn, Virgin Media has been bought by Liberty Global, with the Virgin Group being able to retain a small share of total ownership after the acquisition. In terms of competition, the big players include BT, Vodafone, and a slew of broadband players like BSkyB also making plays in the same set industry. EE also competes in this same space, the firm providingVirgin Mobile with the physical