dr./ ahmed mohamed rabiestaff.du.edu.eg/upfilestaff/1058/101058_a1574422322__.pdf · dr./ ahmed...
TRANSCRIPT
Dr./ Ahmed Mohamed Rabie
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Text Book
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Example 1:- The University database stores details
about university students, courses, the semester a
student took a particular course (and his mark and
grade if he completed it), and what degree program
each student is enrolled in . The database is a long
way from one that’d be suitable for a large institution.
• The university offers one or more programs.
• A program is made up of one or more courses.
• A student must enroll in a program.
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• A student takes the courses that are part of this
program.
• A program has a name, a program identifier, the total
credit points required to graduate, and the year it
commenced.
• A course has a name, a course identifier, a credit
point value, and the year it commenced.
• Students have one or more given names, a surname, a
student identifier, a date of birth, and the year they
first enrolled .
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• When a student takes a course, the year and
semester he attempted it are recorded . When he
finishes the course, a grade (such as A or B) and a
mark (such as 60 percent) are recorded.
• Each course in a program is sequenced into a year
(for example, year 1 )and a semester (for example
‘(semester 1).
Design ER schema for University database.
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Example 2: The Flight database stores details about an
airline’s fleet, flights, and seat bookings. Again, it’s a
hugely simplified version of what a real airline would
use ،but the principles are the same .
• The airline has one or more airplanes.
• An airplane has a model number, a unique
registration number, and the capacity to take one or
more passengers.
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• An airplane flight has a unique flight number, a
departure airport, a destination airport, a departure
date and time, and an arrival date and time.
• Each flight is carried out by a single airplane.
• A passenger has given names, a surname, and a
unique email address.
• A passenger can book a seat on a flight.
Design ER schema for Flight database.
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Example 3:- Design a database to keep track of
information for an Art museum. Assume that the
following requirements were collected:
The museum has a collection of art objects. Each art
object has a unique identification, an artist (if
known), a year (when it was created, if known), a
title, an epoch (Renaissance, Modern, Ancient, etc.),
and a description. The arts objects are classified in
the museum in several ways as discussed below:
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Arts objects are categorized based on their type.
The main types are: painting and sculpture, plus
another type they called “other” to accommodate
objects that do not fall into one of the two main
types.
A painting has a paint type (oil, watercolor, etc.),
material on which it is draw on (paper, canvas,
wood, etc.), and style (modern, abstract,
impressionism, etc.).
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A sculpture has a material from which it was
created (wood, stone, iron, etc.), height, weight,
and style.
An art object in the other category has a type
(print, photo, etc.) and a style.
Art objects are also categorized as permanent
collection that are owned by the museum (which
has information on the date acquired, whether it is
on display or stored, and cost) or borrowed, which
has information on the collection (from which it
was borrowed) date borrowed, and date returned.
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The museum keeps track of artist’s information, if
known: name, date of birth, date of death (if not
living), country of birth, epoch, main style,
description. The name is assumed to be unique.
Different exhibitions occur, each having a name, a
start date, an end date, and are related to all the art
objects that were on display during the exhibition.
Information is kept on other collections with which
the museum interacts, including name (unique),
type (museum, personal, etc.), description, address,
phone, and current contact person. Design EER
schema for Art museum
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Exercise:- The Music Database, the music database
stores details of a personal music library, and could
be used to manage your MP3 ،CD, or vinyl
collection. Because this database is for a personal
collection, it’s relatively simple and stores only the
relationships between artists, albums, and tracks. It
ignores the requirements of many music genres,
making it most useful for storing popular music and
less useful for storing jazz or classical music.
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• The collection consists of albums.
• An album is made by exactly one artist.
• An artist makes one or more albums.
• An album contains one or more tracks
• Artists, albums, and tracks each have a name.
• Each track is on exactly one album.
• Each track has a time length, measured in seconds.
• When a track is played, the date and time the
playback began (to the nearest second) should be
recorded; this is used for reporting when a track
was last played, as well as the number of times
music by an artist, from an album, or a track has
been played.
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Exercise:- Design an ER schema for keeping track
of information about votes taken in the U.S. House of
Representatives during the current two-year
congressional session. The database needs to keep
track of each U.S. STATE’s Name(e.g., ‘Texas’, ‘New
York’, ‘California’) and include the Region of the
state (whose domain is {‘Northeast’, ‘Midwest’,
‘Southeast’, ‘Southwest’, ‘West’}). Each
CONGRESS_PERSON in the House of
Representatives is described by his or her Name, plus
the District represented, the Start_date when the
congressperson was first elected, and the political
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Party to which he or she belongs (whose domain is
{‘Republican’, ‘Democrat’,‘Independent’, ‘Other’}).
The database keeps track of each BILL (i.e., proposed
law), including the Bill_name, the Date_of_vote on
the bill, whether the bill Passed_or_failed (whose
domain is {‘Yes’, ‘No’}), and the Sponsor (the
congressperson(s) who sponsored—that is,
proposed—the bill). The database also keeps track of
how each congressperson voted on each bill (domain
of Vote attribute is {‘Yes’, ‘No’, ‘Abstain’, ‘Absent’}).
Draw an ER schema diagram for this application.
State clearly any assumptions you make.
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Exercise:- The following narrative describes a
simplified version of the organization of Olympic
facilities planned for the summer Olympics. Draw an
EER diagram that shows the entity types, attributes,
relationships, and specializations for this application.
State any assumptions you make. The Olympic
facilities are divided into sports complexes. Sports
complexes are divided into one-sport and multisport
types. Multisport complexes have areas of the
complex designated for each sport with a location
indicator (e.g., center, NE corner, and so on.
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A complex has a location, chief organizing individual, total
occupied area, and so on. Each complex holds a series of
events (e.g., the track stadium may hold many different
races). For each event there is a planned date, duration,
number of participants, number of officials, and so on. A
roster of all officials will be maintained together with the
list of events each official will be involved in. Different
equipment is needed for the events (e.g., goal posts, poles,
parallel bars) as well as for maintenance. The two types of
facilities (one-sport and multisport) will have different
types of information. For each type, the number of
facilities needed is kept, together with an approximate
budget.