DBMS Chapter 1

Question 1

Traditional database application

Answer 1

information is stored and accessed is either textual or numeric.

Question 2

Multimedia database systems

Answer 2

Includes pictures, audio, and video streams

Question 3

Geographic information system (GIS)

Answer 3

Maps, weather data, satellite images

Question 4

Real time/active database technology

Answer 4

Industrial and manufacture database processes

Question 5

Database

Answer 5

Collection of related data

Question 6

Data

Answer 6

Known facts that can be recorded and that have implicit meaning

Question 7

Data warehouses and online analytical processing (OLAP)

Answer 7

Used to extract and analysis useful business information from very large databases to support decision making

Question 8

Mini-world

Answer 8

Some aspect of the real world which is stored in a database

Ex: student grades/ transcripts

Question 9

Database management systems (DBMS)

Answer 9

Collection of programs that enables users to create and maintain a database.

Question 10

DBMS functionality:

Answer 10

Constructing, Manipulating, Shared access, Queries, Defining, Protection, Transactions

Question 11

3 steps to making a database

Answer 11

Conceptual design = ERD
Logical design = Schema
Physical design = SQL

Question 12

Database approach vs File-processing approach

Answer 12

■ Self-describing nature of a database system
■ Insulation between programs and data, and data abstraction
■ Support of multiple views of the data
■ Sharing of data and multi user transaction processing

Question 13

Self-Describing Nature

Answer 13

A DBMS catalog stores the description of the database. The description is called meta-data. This allows the DBMS software to work with different databases

Question 14

Insulating between programs and data

Answer 14

Called program-data independence. Allows changing data storage structures and operations without having to change the DBMS access programs

Question 15

Data Abstraction

Answer 15

A data model is used to hide storage details and present the users with a conceptual view of the database

Question 16

Support of multiple views of the data

Answer 16

Each user may see a different view of the database, which describes only the data of interest to that user

Question 17

Sharing of data and multi-user transaction processing

Answer 17

Allowing a set of concurrent users to retrieve and to update the database. through concurrency control.

Question 18

Concurrency control

Answer 18

Ensures that several users trying to update the same data do so in a so in a controlled manner so that the result of the updates is correct.

Question 19

Transaction

Answer 19

Executing program that includes one or more database accesses, such as reading or updating of database records

Question 20

Database Administration

Answer 20

Responsible for authorization access to the database, for coordinating and monitoring its use, acquiring software and hardware resources, controlling its use and monitoring efficiency of operations

Question 21

Database designers

Answer 21

Define the content the structure, constraints, and function transaction against the database

Question 22

End-users

Answer 22

Use data for queries, reports, update database content

Question 23

Casual end-user

Answer 23

Use database occasionally when needed

Question 24

Naive

Answer 24

Use well-defined function in the form against the database Ex: bank tellers

Question 25

Sophisticated user

Answer 25

People familiar with the system capabilites

Question 26

Stand-alone

Answer 26

Maintain personal databases using ready to use packaged applications Ex: tax programs user

Question 27

Workers behind the Scene

Answer 27

DBMS system designers and implementer Tool developers Operators and maintenance personnel System administration personnel.

Question 28

Advantages of Using the Database Approach

Answer 28

- Controlling redundancy - Sharing of data - Restricting unauthorized access - Providing persistent storage for program Objects - Providing Storage Structures - Providing backup and recovery services. - Providing multiple interfaces to different classes of users. - Representing complex relationships among data. - Enforcing integrity constraints on the database. - Drawing Inferences and Actions using rules

Question 29

Buffering module

Answer 29

Used to copy data from disk to main memory

Question 30

Index

Answer 30

Data structure used to disk search for records

Question 31

Potential for enforcing standards

Answer 31

Standards refer to data item names, display formats, screens, report structures, meta-data (description of data) etc

Question 32

Reduced application development time

Answer 32

incremental time to add each new application is reduced.

Question 33

Flexibility to change data structures

Answer 33

Database structure may evolve as new requirements are defined.

Question 34

Availability of up-to-date information

Answer 34

Very important for on-line transaction systems such as airline, hotel, car reservations.

Question 35

Economies of scale

Answer 35

By consolidating data and applications across departments wasteful overlap of resources and personnel can be avoided.

Question 36

When not to use DBMS

Answer 36

- High initial investment and possible need for additional hardware. - Overhead for providing generality, security, concurrency control, recovery, and integrity functions.

Question 37

When a DBMS may be unnecessary

Answer 37

- If the database and applications are simple, well defined, and not expected to change. - If there are stringent real-time requirements that may not be met because of DBMS overhead. - If access to data by multiple users is not required.

Question 38

When no DBMS may suffice

Answer 38

- If the database system is not able to handle the complexity of data because of modeling limitations - If the database users need special operations not supported by the DBMS.