Questions and Answers of Database Management Systems

The U.S. government wants to keep track of information about states, governors, cities, and mayors. In addition, it wants to maintain data on the various federal agencies and the annual grants each
Consider the General Hardware relational database shown in Figure 7.19.a. Write an SQL command to create the CUSTOMER table.b. Write an SQL command to create a view of the CUSTOMER table that
Write an SQL command to change that responsibility to Salesperson Number 311.e. Write an SQL command to add a new record to the CUSTOMER table for Customer Number 9442. The Customer Name is Smith
A fixed disk consists of six platters. The upper surface of the topmost platter and the lower surface of the bottommost platter are not used for recording data. There are 120 tracks on each recording
A fixed disk has 80 cylinders. The tracks in each cylinder are numbered 0–11. The upper surface of the topmost platter and the lower surface of the bottommost platter are not used for recording
Consider the B+-tree index, below:a. A record has just been added to Cylinder 6, causing a cylinder split. The highest key value on Cylinder 6 is now 2156, the highest key value on Cylinder 20, and
A hashed file has space for 70 records. Relative record numbers of 0–69 label each of the 70 record positions. In addition, there is space for several overflow (synonym) records. Draw a picture of
Consider the following relational database for the Quality Appliance Manufacturing Co. The database is designed to track the major appliances (refrigerators, washing machines, dishwashers, etc.) that
Draw an object-oriented class diagram, including traditional unary, binary, and ternary relationships, as well as generalization and aggregation relationships as needed, to represent the following
Draw an object-oriented class diagram, including traditional unary, binary and ternary relationships, as well as generalization and aggregation relationships as needed, to represent the following
You have just been named Director of Data Administration of General Hardware Co. General Hardware maintains a large central IS organization with several operational relational databases at its
Good Reading Bookstores Database.a. Create a data dictionary TABLES table and an ATTRIBUTES table and enter data in them for Good Reading Bookstores database shown in Figure 7.21. Your answer should
Best Airlines Mechanics Database.a. Create a data dictionary TABLES table and an ATTRIBUTES table and enter data in them for Best Airlines’ mechanics database, shown in Exercise 8.5. Your answer
A large bank has a headquarters location plus several branches in each city in a particular region of the country. As transactions are conducted at each branch, they are processed online against a
The bank in Exercise 1, which it totally dependent on its relational database, must be able to keep running in the event of the failure of any one table on one disk drive, in the event of a major
The Tasty Seafood Restaurant is a large restaurant that specializes in fresh fish and seafood. Because its reputation for freshness is important to Tasty, it brings in a certain amount of each type
Construct examples of the lost update problem, the use of locks, deadlock, and versioning for the case of a joint bank account (i.e. two people with access to the same bank account).
Australian Boomerang, Ltd. wants to design a distributed relational database. The company is headquartered in Perth and has major operations in Sydney, Melbourne, and Darwin. The database involved
Canadian Maple Trees, Inc. has a distributed relational database with tables in computers in Halifax,Montreal,Ottawa, Toronto, andVancouver.The database consists of twelve tables, some of which are
Consider the Happy Cruise Lines relational database in Minicase 5.1.The company has decided to reconfigure this database as a distributed database among its major locations: New York, which is its
Consider the Super Baseball League relational database in Minicase 5.2. The league has decided to organize its database as a distributed database with replicated tables. The nodes on the distributed
Video Centers of Europe, Ltd. data warehouse:a. Design a multidimensional database using a star schema for a data warehouse for the Video Centers of Europe, Ltd. business environment described in the
Best Airlines, Inc., data warehouse:In the exercises in Chapter 8, we saw the following relational database, which Best Airlines uses to keep track of its mechanics, their skills, and their airport
Happy Cruise Lines data warehouse:a. Design a multidimensional database using a star schema for a data warehouse for the Happy Cruise Lines business environment described in Minicase 2.1. The subject
Super Baseball League data warehouse:a. Design a multidimensional database using a star schema for a data warehouse for the Super Baseball League business environment described in Minicase 2.2. The
Consider Lucky Rent-A-Car’s Web site, which contains its database, as described in Figure 5.18.Describe, in detail, the steps taken in both hardware and software to reach the database when a
Consider the World Music Association’s Web site, which contains its database, as described in Figure 5.17. Describe, in detail, the steps taken in both hardware and software to reach the database
Describe three different uses for non-traditional data types in the Web sites of:a. Good Reading Bookstores.b. World Music Association.c. Lucky Rent-A-Car.
Happy Cruise Lines.a. Consider Happy Cruise Lines’ Web site, which contains its database, as described in Minicase 5.1.Describe, in detail, the steps taken in both hardware and software to reach
Super Baseball League.a. Consider the Super Baseball League’s Web site, which contains its database, as described in Minicase 5.2. Describe, in detail, the steps taken in both hardware and software
Why was the commercial introduction of relational database delayed during the 1970s? What factors encouraged its introduction in the early 1980s?
How does a relation differ from an ordinary file?
Define the terms ‘‘tuple’’ and ‘‘attribute.’’
What are the characteristics of a candidate key?
What is a primary key? What is an alternate key?
Define the term ‘‘foreign key.’’
In your own words, describe how foreign keys are used to set up one-to-many binary relationships in relational databases.
Describe why an additional relation is needed to represent a many-to-many relationship in a relational database.
Describe what intersection data is, what it describes, and why it does not describe a single entity.
What is a one-to-one binary relationship?
Describe the purpose and capabilities of:a. The relational Select operator.b. The relational Project operator.c. The relational Join operator.
Describe how the join operator works.
Describe the concept of the unary one-to-many relationship.
How is a unary one-to-many relationship constructed in a relational database?
Describe the concept of the unary many-to-many relationship.
How is a unary many-to-many relationship constructed in a relational database?
Describe the concept of the ternary relationship.
How is a ternary relationship constructed in a relational database?
Is a ternary relationship the equivalent of the three possible binary relationships among the three entities involved? Explain.
Describe the problem of referential integrity.
Compare and contrast the three delete rules: restrict, cascade, and set-to-null.
What is logical database design?
What is physical database design and how does it relate to logical database design?
In general terms, describe the main logical database design techniques and how they relate to one another.
Based on an entity-relationship diagram, how can you determine how many tables there will be in the corresponding relational database?
Describe the process for converting entities in each of the following relationships into relational database structures:a. One-to-one binary relationship.b. One-to-many binary relationship.c.
Describe the data normalization process including its specific steps. Why is it referred to as a ‘‘decomposition process?’’
Explain the following terms:a. Functional dependency.b. Determinant.
What characterizes unnormalized data?Why is such data problematic?
What characterizes tables in first normal form? Why is such data problematic?
What is a partial functional dependency? What does the term ‘‘fully functionally dependent’’ mean?
What is the rule for converting tables in first normal form to tables in second normal form?
What is the definition of data in second normal form?
What is a transitive dependency?
What is the rule for converting tables in second normal form to tables in third normal form?
What is the definition of data in third normal form?
What are the characteristics of data in third normal form?
How can data normalization be used to check the results of the E-R diagram-to-relational database conversion process?
What SQL command do you use to produce a new table structure? What SQL command do you use to discard a table?
What is a view? What SQL commands do you use to produce a new view and to discard one that is no longer needed?
What are the SQL data manipulation commands and what are their functions?
Describe the following disk concepts or components.a. Platter and recording surface.b. Track.c. Cylinder.d. Read/write head.e. Access-arm mechanism.
Why is it important to store files on a cylinder-bycylinder basis?
Describe the four steps in the transfer of data from disk to primary memory.
What is a file organization? What is an access method? What do they accomplish?
What is an index? Compare the concept of the index in a book to an index in an information system.
Describe the idea of the simple linear index. What are its shortcomings?
What is an indexed-sequential file?
Describe the idea of the B+-tree index. What are its advantages over the simple linear index?
Describe how a direct search works using a B+-tree index.
Describe what happens to the index tree when you insert new records into a file with a B+-tree index.
Answer the following general questions about indexes:a. Can an index be built over a non-unique field?b. Can an index be built over a field if the file is not stored in sequence by that field?c. Can
Describe the idea of the hashed file. What are its advantages and disadvantages in comparison to indexes?
Describe how a direct search works in a hashed file using the division-remainder method of hashing.
What is a collision in a hashed file? Why do collisions occur? Why are they of concern in the application environment?
What is physical database design?
Describe why physical database design is necessary.
Explain why the need to perform joins is an important factor affecting application and database performance.
Why does the degree to which data is dispersed over a disk affect application and database performance?
Explain why the volume of data access operations can adversely affect application and database performance.
Which ‘‘input’’ is the starting point for physical database design?
Describe how response time requirements and throughput requirements determine the overall performance level of the application and database environment.
Describe the characteristics of the data in the database that must be considered as inputs to the physical database design process. Why are they important?
Describe the characteristics of the applications that must be considered as inputs to the physical database design process. Why are they important?
Why do DBMS and hardware characteristics have to be taken into account in the physical design process?
Explain the statement, ‘‘Some physical database design techniques change the logical design and some do not.’’
What attributes should be considered as candidates for having indexes built on them? What is the potential problem with building too many indexes?
What is a ‘‘view’’? Which factors affecting application and database performance can be dealt with by using views? Explain.
Describe the ‘‘clustering files’’ technique. What advantage is gained by using it? What is its disadvantage?
What is the difference between horizontal and vertical partitioning? What is their common advantage?Are their disadvantages the same or different?Explain.

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