Entity-Relationship (E/R) Model Dr P Sreenivasa Kumar Professor CS&E Dept I I T Madras Entity-Relationship (E/R) Model Widely used conceptual level data model • proposed by Peter P Chen in 1970s Data model to describe the database system at the requirements collection stage • high level description. • easy to understand for the enterprise managers. • rigorous enough to be used for system building. Concepts available in the model • entities and attributes of entities. • relationships between
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nsportation has changed over time. Most of everything has changed even transportation has changed and business has also changed. Transportation has changed all types of cars and planes have changed now they use gas and charger’s . Cars run off gas and charger’s cause of all the things we have to use to make them. They use gas witch we have to pay for and it’s not cheap. Planes help a lot they are way faster than cars so are trains. The cars back than can not be charged or fixed we they didn’t
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The Everglades: A Food Web Diagram Name BIO/101 Date Dr. Doreen Sterling The Everglades: A Food Web Diagram The Everglades is a two million acre wetland ecosystem. The Everglades reaches from central Florida‚ near Orlando‚ all the way south to Florida Bay (National Wildlife Federation‚ 1996-2013). During the wet season‚ Lake Okeechobee overflows‚ releasing water into a slow moving‚ shallow river. The river is mostly saw-grass marsh. The Everglades is an ecosystem that hosts a large diversity
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Set Operations and Venn Diagrams " Please respond to the following: QUES: Create a story problem that demonstrates how a Venn diagram could be used to illustrate combined operation with sets. ANS: Use a Venn diagram to illustrate the following scenario: There are 40 people in a drum corp. Of the 40 people‚ 20 play the snare drum; 10 play the trumpet; 5 plays the cymbals. There are 5 people that play both the snare drum and cymbals; and 3 play all three instruments. How many people don’t play
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Relationship Diagram #2. a. & b. One Room can be designated only one Room Type‚ whilst a particular Room Type can be assigned to several rooms (i.e. there may be many rooms that have double beds). Therefore‚ Room has a one-to-one relationship with RoomType and RoomType has a one-to-many relationship with Room. From the table‚ it can be seen that a particular room can only be designated as belonging to one type / category‚ thus confirming that Room RoomType has a one-one relationship
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Genetically Modified Organisms Course Project Table of Contents Abstract-------------------------------------------------------------------------------------------------------3 Introduction to Genetically Modified Foods/The History behind the Technology--------------4-7 Political and Legal Influences/Economics and GM Foods------------------------------------------7-11 Psychological/Sociological Effects of GMOs/Cultural Context and media Influence---------11-15 Genetically
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Global warming and its consequences are rather alarming. One talks about the need of saving the environment - here is a list of simple things you can do to actually contribute to save the environment instead of just discussing it or suffering the consequences of it. 1) Plant trees or save trees: Think green. Saving trees will also help save wildlife. The destruction of trees is the primary cause that global warming is taking place today. So if you can just plant as many trees as you can and ENSURE
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Nowadays‚ our environment is becoming worse and some people have started to believe that people have to save the world for the new generation. Global warming is one of the most serious problems now‚ but some people do not care about the environment and keep producing pollution. We can see that there are a lot of animals or plants that are dying because of the high temperatures. Improving the environment has many different solutions such as transportation‚ turning off the electric appliances and
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How Acid Rain Affects Organisms in Aquatic Biomes Through the advancement of technology‚ the issue of the air surrounding the earth might have been one of the most often matters to be brought up and discussed among scientists and engineers. Acid rain is one of the more serious environmental problems and it is closely related to the air pollution. Nowadays‚ it has affected large part of US‚ Europe and Canada. People start to be concerned about acid rain since it is getting worse in the passed
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In the novel Great Expectations by Charles Dickens‚ the author describes a young poor boy as innocent‚ fragile‚ and ignorant. But throughout the novel that little boy‚ Pip‚ grows to become knowledgeable‚ ashamed‚ and ungrateful. The theme for this novel is even though one becomes successful in life one should never feel embarrassed and ashamed towards the people who helped one succeed and most important one should never forget where one came from. Becoming successful in life is something to be
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