Chapter1

Question 1

Data

Answer 1

is numeric, textual, visual, or audio information that describes real-world systems.

Question 2

Scope

Answer 2

The amount of data produced and collected can vary. Ex: A small business might track an inventory of a few thousand items, bu t a large commerce website might
track billions of items.

Question 3

Format

Answer 3

Data may be produced as numbers, text, images, audio, or video. Ex: A phone’s proximity sensor generates raw numbers, and a s atellite captures images

Question 4

Access

Answer 4

Some data sources are private while others are made publicly available.

Question 5

database

Answer 5

is a collection of data in a structured format. In principle, databases can be stored on paper or even clay tablets

Question 6

database system

Answer 6

also known as a database management system or DBMS, is software that reads and writes data in a database.

Question 7

query

Answer 7

is a request to retrieve or change data in a database.

Question 8

database application

Answer 8

software that helps business users interact with database systems.

Question 9

database administrator

Answer 9

is responsible for securing the database system against unauthorized users. A database administrator enforces procedures for user access
and database system availability.

Question 10

database designer

Answer 10

determines the format of each data element and the overall database structure.

Question 11

database programmer

Answer 11

develops computer programs that utilize a database. Database programmers write applications that combine database query langu ages and
general-purpose programming languages. Query languages and general-purpose languages have significant differences, so database programming is a specialized
challenge.

Question 12

database user

Answer 12

is a consumer of data in a database. Database users request, update, or use stored data to generate reports or information

Question 13

Performance

Answer 13

When many users and applications simultaneously access large databases, query response time degrades rapidly. Database syst ems maintain fast
response times by structuring data properly on storage media and processing queries efficiently.

Question 14

Authorization

Answer 14

Many database users should have limited access to specific tables, columns, or rows of a database. Database systems authori ze individual users to access
specific data.

Question 15

Security

Answer 15

Database systems ensure authorized users only access permissible data. Database systems also protect against hackers by enc rypting data and restricting
access.

Question 16

Rules

Answer 16

Database systems ensure data is consistent with structural and business rules.

Question 17

transaction

Answer 17

is a group of queries that must be either completed or rejected as a whole.

Question 18

database system is composed of

Answer 18

query processor, storage manager, transaction manager, log, and catalog

Question 19

relational database

Answer 19

stores data in tables, columns, and rows, similar to a spreadsheet. All data in a column has the same
format.

Question 20

query

Answer 20

is a command for a database that typically inserts new data, retrieves data, updates data, or
deletes data from a database

Question 21

query language

Answer 21

is a computer programming language for writing database queries.

Question 22

SQL statement

Answer 22

is a complete, executable database command.

Question 23

INT

Answer 23

stores integer values

Question 24

DECIMAL

Answer 24

stores fractional numeric values

Question 25

VARCHAR

Answer 25

stores textual values

Question 26

DATE

Answer 26

stores year, month, and day

Question 27

database design

Answer 27

is a specification of database objects such as tables, columns, data types, and indexes. Database design also refers to the process used to develop the specification.

Question 28

Conceptual design

Answer 28

has many alternative names, such as analysis, data modeling, and requirements definition

Question 29

logical design

Answer 29

phase implements database requirements in a specific database system. For relational database systems, logical design converts entities, relationships, and attributes into tables, keys, and columns

Question 30

physical design

Answer 30

phase adds indexes and specifies how tables are organized on storage media. Ex: Rows of a table may be sorted on the values of a column and stored in sort order. Physical design is specified with SQL statements such as CREATE INDEX and, like logical design, is specific to a database system.

Question 31

data independence.

Answer 31

The principle that physical design never affects query results

Question 32

An application programming interface, or API

Answer 32

is a library of procedures or classes that links a host programming language to a database. The host language calls library procedures, which handle details such as connecting to the database, executing queries, and returning results. Ex: JDBC is a library of Java classes that access relational databases.