Questions and Answers of Database Design Using Entity Relationship Diagrams

A tree is classifed as a “large oak tree about 100 years old.” What are three facts about this tree?
Why is the piece of paper not a database of trees?
Another tree has the following characteristics: pine, small, 15 years old. If I write the information about the oak and pine trees on a piece of paper, could you consider this a database? Why or why
You have a set of books on bookshelves in your house. Someone asks you to create a list of all the books you have.1. Who is going to use this list?2. When the list is completed, will it be a
In what phase is the database created?
Which person tests the database?
In what phase does the user say what is wanted in the database?
When you are recording facts about a database, what phase is that?
Briefy describe the major steps of the SE life cycle as it applies to databases.
Who are the two main players in the sofware development life cycle?
Why is written communication between the parties in the design process important?
What is the blueprint from which the actual database is created called?
What are the three important phases of designing a database?
David operates a golf shop with golf equipment and many customers; his primary business is selling retail goods to customers. David wants to keep track of everything on a computer. He approaches
What does it mean to say a field has unique values?
Why is it desirable to have a key be unique?
Why does a file have to be organized by a key field?
What does null mean?
Consider this customer file:What is wrong here?
What is COBOL?
Why is ordering important in a sequential filing system?
What is a database program?
In the early days, how was data put into a file?
What are the three main data models we have discussed?
Which data model is mostly used today? Why?
What are some of the disadvantages of the hierarchical data model?
What are some of the disadvantages of the network data model?
How are all relationships (mainly the cardinalities) described in the hierarchical data model? How can these be a disadvantage of the hierarchical data model?
What are structural constraints?
How are all relationships (mainly the cardinalities) described in the network data model? Would you treat these as advantages or disadvantages of the network data model?
Why was Codd’s promise of the relational model better?
Is the following arrangement of data a table?
Is the following arrangement of data a table?
Is the following arrangement of data a table?
Is the following arrangement of data a table?
Is the following arrangement of data a table?
What does R(A, B, C, D, E, F) mean?
In the following table, does all the data conform to empno → name?
Does the fact that the data conforms to the proposed FD prove the FD is in fact true?
In the following table, does all the data conform to empno → name?
In the following table, does all the data conform to empno → name?
In the following table, does empno → name?
What would you suppose is the key of this table?
Put this arrangement of data into 1NF:
Given AB→ CDE, is R(A, B, C, D, E) in 2NF?
Given B→ ACDE, is R(A, B, C, D, E) in 2NF?
Given AB→ CDE and B → E is R(A, B, C, D, E) in 2NF?
If a table is in the 1NF and you have no concatenated key, you do not have to worry about 2NF problems (True/False)?
Consider this table:with FDsandIs this table in 1NF, 2NF, 3NF? Decompose the table if necessary.
Consider this table:with FDsIs this table in 1NF, 2NF, 3NF? Decompose the table if necessary.
For each of the following, find a minimal key and decompose as necessary to reach the 3NF. Show decomposed tables with keys.
If X → Y, can you say X → Y? Why or why not?
Decompose the following data into 1NF tables:Khanna, 123 4th St., Columbus, Ohio {Delhi University, Calcutta University, Ohio State} Ray, 4 Moose Lane, Pensacola, Florida {Zambia University,
Consider the data in Table 3.30.and the following FDs:Decompose as necessary to achieve 3NF.
Of the following items, determine which could be an entity and state why: automobile, college class, student, name of student, book title, number of dependents.
Why are entities not called files or records?
What are entity sets?
Why do we need entity-relationship diagrams?
What are attributes? List attributes of the entities you found in question 1?Question 1:Of the following items, determine which could be an entity and state why: automobile, college class, student,
Describe the basic types of data representation schemas used in ER modeling.
What notation is used to diagrammatically show an entity in the Chen-like ER model?
How do we diagrammatically show attributes in the Chen-like ER model?
How do we show composite attributes in the Chen-like ER model?
Draw an entity representation for the entity BUILDING with the following attributes: building name, occupancy, and whether or not it has an elevator (yes/no).
How do you map multivalued attributes?
How do you map composite attributes?
What is a unique identifier? Is it a candidate key? Is it “the” primary key? Discuss.
You want to create a database about businesses. Each business will have a name, address, the business phone number, the owner's phone number, and the frst names of the employees who work at the
You want to create a database about the books on your shelf. Each book has authors (only the last name is needed), title, publisher, courses used in (course number only). Draw the ER diagram using
Can the nature of an entity change over time? Explain.
What are the diferences between an entity and a relationship?
When would it be preferable to consider an attribute an entity?
Does it make sense to have an entity with one attribute? Why or why not?
Are relationships between two entities permanent, or can the nature of this relationship change over time?
Are attributes of an entity permanent?
Does there always exist a relationship between two entities?
Draw an ER diagram (using the Chen-like model) for an entity called HOTEL and include no fewer than fIve attributes for the entity. Of the fIve attributes, include at least one composite attribute
Suppose we reconsider our STUDENT example, and the only attributes of student are Student name and name. Let us suppose we have another entity called HIGH SCHOOL —the high school from which the
Suppose a college had one dormitory with many rooms. The DORMITORY entity, which is actually a “dormitory room” entity since there is only one dorm. Dormitory has the attributes room number and
If we have two entities, a PLANE and a PILOT, and describe the relationship between the two entities asWhat should the relationship read from the side of the other entity?
Complete the methodology by adding sample data to Figures 5.3, 5.5, and Exercises 5.1, 5.2, 5.3, and 5.4.FIGURE 5.3Exercises 5.1Draw an ER diagram (using the Chen-like model) for an entity called
What are structural constraints?
What kind of information does the cardinality ratio give us?
In how many different ways can two entities be involved in a cardinality relationship? Give examples.
What kind of information does the participation constraint give us?
Is it always necessary to have cardinality ratios as well as participation constraints in the same ER diagram? Why? Explain.
Sketch an ER diagram showing the participation ratios (full/ partial) and cardinalities for the following:a. Students must be advised by one advisor, and an advisor can advise many students.b.
Give an example of a 1(full):1 relationship? Does such a relationship always have to be mandatory? Explain with examples.
Give an example of a 1(partial):1 relationship? Does such a relationship always have to be optional? Explain with examples.
Give an example of a M(full):N relationship? Would such a relationship always be optional or mandatory? Explain with examples.
Give an example of a M(partial):N relationship? Would such a relationship always be optional or mandatory? Explain with examples.
State the mapping rule(s) that would be used to map Figure 6.14. Map Figure 6.14 to a relational database and show some sample data.
State the mapping rule(s) that would be used to map Figure 6.17. Map Figure 6.17 to a relational database and show some sample data.
Let us reconsider our student example in Exercise 5.2 in which the only attributes of student are Student_number and name Now we have another entity called HIGH SCHOOL, which is going to be the high
Suppose that a college had one dormitory with many rooms. The dormitory entity, which is a DORMITORY ROOM entity since there is only one dorm, has the attributes room number and single/double
Consider a STUDENT database with students and campus organizations. Students will have the attributes of student number and student name ORGANIZATIONS will have the attributes organizations name and
Consider a STUDENT and ADVISOR database. Students have a student number and student name. Advisors have names, of ce numbers, and advise in some major. Te major the advisor advises in is designated
You want to record the following data in a database: restaurant name and location, employee names and IDs, capacity of restaurant, smoking or nonsmoking area in restaurant, hours of operation for
Record the following data in a database: business name, owner, location(s), telephone numbers, delivery truck number, truck capacity, usual route description (e.g., North, West, Central, Lake, . .
Refer to Figure 6.19. What are the English language statements you can make about the figure?Figure 6.19

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