Databases: Ch 1 & 2

True

A data model is usually graphical

True

A data warehouse can store data derived from many sources.

Single-user

A desktop database is a database.

False

A disadvantage of the relational database management system (RDBMS) is its inability to hide the complexities of the relational model from the user.

Field

A is a character or group of characters that has a specific meaning.

File

A is a collection of related records.

Record

A is a logically connected set of one or more fields that describes a person, place, or thing.

Multiuser

A workgroup database is a(n) database.

Modle

A(n) 's main function is to help one understand the complexities of the realworld environment.

Enterprise

A(n) database is used by an organization and supports many users across many departments.

Workgroup

A(n) database supports a relatively small number of users (usually fewer than 50) or a specific department within an organization.

Data anomaly

A(n) develops when all required changes in the redundant data are not made successfully.

DBMS (database management system) database management

A(n) is a collection of programs that manages the database structure and controls access to the data stored in the database.

Constraints

A(n) is a restriction placed on the data.

Query

A(n) is a specific request issued to the DBMS for data manipulation.

Ad hoc query

A(n) is a spur-of-the-moment question.

Enity

A(n) is anything about which data are to be collected and stored.

Relationship

A(n) is bidirectional.

Attribute

A(n) is the equivalent of a field in a file system.

Application

A(n) might be written by a programmer or it might be created through a DBMS utility program.

Enity

A(n) represents a particular type of object in the real world.

Good decision making

Accurate, relevant, and timely information is the key to .

Semistructured

An XML database supports the storage and management of XML data.

False

An advantage of database systems is that you needn't perform frequent updates and apply latest patches.

False

An implementation-ready data model needn't necessarily contain enforceable rules to guarantee the integrity of the data.

True

An implementation-ready data model should contain a description of the data structure that will store the end-user data.

False

An operational database is sometimes referred to as an enterprise database

False

Business rules apply to businesses and government groups, but not to other types of organizations such as religious groups or research laboratories.

True

Business rules must be rendered in writing.

False

Corporations use only structured data.

False

Data and information are essentially the same thing.

False

Data anomaly is defined as the condition in which all of the data in the database are consistent with the real-world events and conditions.

True

Data constitute the building blocks of information.

The data always yields consistent results

Data is said to be verifiable if:

False

Data is the result of processing raw facts to reveal its meaning.

True

Data processing can be as simple as organizing data to reveal patterns.

Operational databases

Data warehouse contains historical data obtained from the

False

Database designers determine the data and information that yield the required understanding of the entire business.

False

Database programming languages receive all application requests and translate them into the complex operations required to fulfill those requests.

The metadata describe the data characteristics and the set of relationships that links the data found within the database. For example, the metadata component stores information such as the name of each data element, the type of values (numeric, dates, or text) stored on each data element, and whether the data element can be left empty.

Describe what metadata are and what value they provide to the database system.

Proper database design requires the designer to identify precisely the database's expected use. Designing a transactional database emphasizes accurate and consistent data and operational speed. Designing a data warehouse database emphasizes the use of historical and aggregated data. Designing a database to be used in a centralized, single-user environment requires a different approach from that used in the design of a distributed, multiuser database.

Discuss some considerations when designing a database.

True

Each row in the relational table is known as an entity instance or entity occurrence in the ER model.

Raw facts of interest to the end user

End-user data is .

True

Even when a good database blueprint is available, an applications programmer's view of the data should match that of the manager and the end user.

False

Field refers to a collection of related records.

False

In Chen notation, entities and relationships have to be oriented horizontally; not vertically.

False

In an SQL-based relational database, each table is dependent on every other table.

True

In the context of data models, an entity is a person, place, thing, or event about which data will be collected and stored.

Data

Information is produced by processing

True

M:N relationships are not appropriate in a relational model.

True

Metadata describe the data characteristics and the set of relationships that links the data found within the database.

Semistructured

Most data that can be encountered are best classified as .

False

One advantage of a database system over previous data management approaches is that the database system is considerably less complex.

True

One disadvantage of a database system over previous data management approaches is increased costs.

False

One disadvantage of the DBMS is that it increases the risk of data security

Formatted

Raw data must be properly for storage, processing and presentation.

False

Structural dependence exists when it is possible to make changes in the file structure without affecting the application program's ability to access the data.

many- to -many

Students and classes have a relationship.

False

The DBMS reveals much of the database's internal complexity to the application programs and users

Data dictionary

The DBMS uses the to look up the required data component structures and relationships, thus relieving programmers from having to code such complex relationships in each program.

Collection of files

The database structure in a DBMS is stored as a .

False

The external model is the representation of the database as "seen" by the DBMS.

False

The hierarchical model is software-independent.

True

The network model has structural level dependence.

True

The only way to access the data in a database is through the DBMS.

Its expected use

The organization of data within folders in a manual file system is determined by .

False

The relational model is hardware-dependent and software-independent.

Query result set

The response of the DBMS to a query is the .

True

The same data might be simultaneously structured and unstructured depending

Database system

The term refers to an organization of components that define and regulate the collection, storage, management and use of data within a database environment.

Island of information

The term refers to scattered locations storing the same basic data.

Context

To reveal meaning, information requires .

True

Today, most relational database products can be classified as object/relational.

A brief explanation of the evolution of file system data processing can be helpful in understanding the data access limitations that databases attempt to overcome. Understanding these limitations is relevant to database designers and developers because database technologies do not make these problems magically disappear—database technologies simply make it easier to create solutions that avoid these problems.

What are some reasons for studying file systems?

Having a DBMS between the end user's applications and the database offers some important advantages. First, the DBMS enables the data in the database to be shared among multiple applications or users. Second, the DBMS integrates the many different users' views of the data into a single all encompassing data repository.

What are the advantages of having the DBMS between the end user's applications and the database?

False

When data are entered into a form and saved, they are placed in the underlying

They enhance the user's ability to undserstand the data

Which of the following is true of spreadsheet applications?

Data Redundancy

Which of the following refers to the situation where different versions of the same data are stored at different places because they weren't updated consistently?

True

Within the database environment, a data model represents data structures with the purpose of supporting a specific problem domain.

Constraints

are normally expressed in the form of rules.

Structured data

are the result of formatting disorganized data in order to facilitate storage, use and generation of information.

Unstructure

data exist in a format that does not lend itself to processing that yields information.

Unstructured

data exist in the format in which they were collected.

Analytical

databases focus primarily on storing data used to generate information required to make tactical or strategic decisions.

Data inconsistency

exists when different and conflicting versions of the same data appear in different places.

Data inconsistency

exists when different versions of the same data appear in different places.

Data independence

exists when it is possible to make changes in the data storage characteristics without affecting an application program's ability to access data.

Data redundancy

exists when the same data are stored unnecessarily at different places.

XML (Extensible Markup Language)

is a special language used to represent and manipulate data elements in a textual format.

Metadata

is data about data through which the end-user data are integrated and managed.

Data integrity

is defined as the condition in which all of the data in the database are consistent with the real-world events and conditions.

Knowledge

is the body of information and facts about a specific subject.

Information

is the result of processing raw data to reveal its meaning.

Information

is the result of revealing the meaning of raw facts.

Metadata

provide a description of the data characteristics and the set of relationships that link the data found within the database.

In-memory databases

refer to a type of database that stores most of its data in RAM rather than in hard disks.

Performance turning

relates to activities that make a database operate more efficiently in terms of storage and access speed.

Performance tuning

relates to the activities that make the database execute transactions more efficiently in terms of storage and access speed.

DBMSs

serve as the intermediary between the user and the database.