Databases: Ch 1 & 2

Data and information are essentially the same thing.
False
Data processing can be as simple as organizing data to reveal patterns.
True
Data is the result of processing raw facts to reveal its meaning.
False
When data are entered into a form and saved, they are placed in the underlying
False
Data constitute the building blocks of information.
True
Metadata describe the data characteristics and the set of relationships that links the data found within the database.
True
The only way to access the data in a database is through the DBMS.
True
Database programming languages receive all application requests and translate them into the complex operations required to fulfill those requests.
False
The DBMS reveals much of the database’s internal complexity to the application programs and users
False
One disadvantage of the DBMS is that it increases the risk of data security
False
An operational database is sometimes referred to as an enterprise database
False
A data warehouse can store data derived from many sources.
True
The same data might be simultaneously structured and unstructured depending
True
Corporations use only structured data.
False
Field refers to a collection of related records.
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.
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.
False
An advantage of database systems is that you needn’t perform frequent updates and apply latest patches.
False
One disadvantage of a database system over previous data management approaches is increased costs.
True
One advantage of a database system over previous data management approaches is that the database system is considerably less complex.
False
is the result of revealing the meaning of raw facts.
Information
is the body of information and facts about a specific subject.
Knowledge
Accurate, relevant, and timely information is the key to .
Good decision making
End-user data is .
Raw facts of interest to the end user
provide a description of the data characteristics and the set of relationships that link the data found within the database.
Metadata
serve as the intermediary between the user and the database.
DBMSs
The database structure in a DBMS is stored as a .
Collection of files
A(n) might be written by a programmer or it might be created through a DBMS utility program.
Application
exists when different versions of the same data appear in different places.
Data inconsistency
refer to a type of database that stores most of its data in RAM rather than in hard disks.
In-memory databases
The response of the DBMS to a query is the .
Query result set
A(n) database is used by an organization and supports many users across many departments.
Enterprise
A(n) database supports a relatively small number of users (usually fewer than 50) or a specific department within an organization.
Workgroup
A workgroup database is a(n) database.
Multiuser
is defined as the condition in which all of the data in the database are consistent with the real-world events and conditions.
Data integrity
A desktop database is a
database.
Single-user
Data warehouse contains historical data obtained from the
Operational databases
Data is said to be verifiable if:
The data always yields consistent results
data exist in the format in which they were collected.
Unstructured
data exist in a format that does not lend itself to processing that yields information.
Unstructure
are the result of formatting disorganized data in order to facilitate storage, use and generation of information.
Structured data
Most data that can be encountered are best classified as .
Semistructured
Which of the following is true of spreadsheet applications?
They enhance the user’s ability to undserstand the data
An XML database supports the storage and management of XML data.
Semistructured
The organization of data within folders in a manual file system is determined by .
Its expected use
A is a logically connected set of one or more fields that describes a person, place, or thing.
Record
A is a collection of related records.
File
A is a character or group of characters that has a specific meaning.
Field
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?
Data Redundancy
The term refers to an organization of components that define and regulate the collection, storage, management and use of data within a database environment.
Database system
relates to the activities that make the database execute transactions more efficiently in terms of storage and access speed.
Performance tuning
is the result of processing raw data to reveal its meaning.
Information
To reveal meaning, information requires .
Context
Raw data must be properly for storage, processing and presentation.
Formatted
Information is produced by processing
Data
is data about data through which the end-user data are integrated and managed.
Metadata
A(n) is a collection of programs that manages the database structure and controls access to the data stored in the database.
DBMS (database management system)
database management
A(n) is a specific request issued to the DBMS for data manipulation.
Query
databases focus primarily on storing data used to generate information required to make tactical or strategic decisions.
Analytical
is a special language used to represent and manipulate data elements in a textual format.
XML (Extensible Markup Language)
A(n) is a spur-of-the-moment question.
Ad hoc query
exists when it is possible to make changes in the data storage characteristics without affecting an application program’s ability to access data.
Data independence
The term refers to scattered locations storing the same basic data.
Island of information
exists when different and conflicting versions of the same data appear in different places.
Data inconsistency
exists when the same data are stored unnecessarily at different places.
Data redundancy
A(n) develops when all required changes in the redundant data are not made successfully.
Data anomaly
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.
Data dictionary
relates to activities that make a database operate more efficiently in terms of storage and access speed.
Performance turning
Describe what metadata are and what value they provide to the database system.
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.
What are the advantages of having the DBMS between the end user’s applications and the database?
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.
Discuss some considerations when designing a database.
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.
What are some reasons for studying file systems?
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.
Describe the five types of users identified in a database system.
A data model is usually graphical
True
An implementation-ready data model needn’t necessarily contain enforceable rules to guarantee the integrity of the data.
False
An implementation-ready data model should contain a description of the data structure that will store the end-user data.
True
Within the database environment, a data model represents data structures with the purpose of supporting a specific problem domain.
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.
True
In the context of data models, an entity is a person, place, thing, or event about which data will be collected and stored.
True
Database designers determine the data and information that yield the required understanding of the entire business.
False
Business rules apply to businesses and government groups, but not to other types of organizations such as religious groups or research laboratories.
False
Business rules must be rendered in writing.
True
In an SQL-based relational database, each table is dependent on every other table.
False
A disadvantage of the relational database management system (RDBMS) is its inability to hide the complexities of the relational model from the user.
False
Each row in the relational table is known as an entity instance or entity occurrence in the ER model.
True
In Chen notation, entities and relationships have to be oriented horizontally; not vertically.
False
M:N relationships are not appropriate in a relational model.
True
Today, most relational database products can be classified as object/relational.
True
The network model has structural level dependence.
True
The external model is the representation of the database as “seen” by the DBMS.
False
The hierarchical model is software-independent.
False
The relational model is hardware-dependent and software-independent.
False
A(n) ‘s main function is to help one understand the complexities of the realworld environment.
Modle
A(n) represents a particular type of object in the real world.
Enity
A(n) is anything about which data are to be collected and stored.
Enity
A(n) is the equivalent of a field in a file system.
Attribute
A(n) is bidirectional.
Relationship
A(n) is a restriction placed on the data.
Constraints
are normally expressed in the form of rules.
Constraints
Students and classes have a relationship.
many- to -many
From a database point of view, the collection of data becomes meaningful only when it reflects properly defined
Business rules
Which of the following is true of business rules?
They can serve as a communication tool between the users and designers
A noun in a business rule translates to a(n) in the data model.
Enity
A verb associating two nouns in a business rule translates to a(n) in the data model.
Realtionship
The hierarchical data model was developed in the
1960s
The object-oriented data model was developed in the
1980s
VMS/VSAM is an example of the .
File system data model
Oracle 11g is an example of the .
XML/Hybrid data model
MySQL is an example of the
Relational data model
In the model, the basic logical structure is represented as an upside-down tree.
Hierarchical
In the model, each parent can have many children, but each child has only one parent.
Hierarchical
The relational data model was developed in the .
1970s
In the model, the user perceives the database as a collection of records in 1:M relationships, where each record can have more than one parent.
Network
The model was developed to allow designers to use a graphical tool to examine structures rather than describing them with text.
Entity realtionship
A(n) enables a database administrator to describe schema components.
Data definition language(DDL)
Which of the following types of HDFS nodes stores all the metadata about a file system?
Name node
Which of the following types of HDFS nodes acts as the interface between the user application and the HDFS?
Client node
Which of the following is a disadvantage of the hierarchical data model?
It does not have standards
NoSQL databases:
provide fault tolerance
The model uses the term connectivity to label the relationship types.
Entity relationship
Which of the following is true of NoSQL databases?
They are not based on the relational
The data model is said to be a semantic data model.
object-oriented
The data model uses the concept of inheritance.
object-oriented
One of the limitations of the model is that there is a lack of standards.
hierarchical
The model is the end users’ view of the data environment.
external
An internal refers to a specific representation of an internal model, using the database constructs
schema
A(n) is a relatively simple representation of more complex real-world data structures.
data model
A(n) is a brief, precise, and unambiguous description of a policy, procedure, or principle within a specific organization.
business rule
A(n) in a hierarchical model is the equivalent of a record in a file system.
segment
A(n) is the conceptual organization of an entire database as viewed by a database administrator.
schema
The relational model’s foundation is a mathematical concept known as a
relation
Each row in a relation is called a(n)
tuple
Each column in a relation represents a(n)
attribute
A(n) defines the environment in which data can be managed and is used to work with the data in the database.
data manipulation language (DML)
Each row in the relational table is known as a(n)
entity instance
In , a three-pronged symbol represents the “many” side of the relationship.
Crow’s Foot notation
A(n) is a collection of similar objects with a shared structure and behavior.
class
In objectoriented terms, a(n) defines an object’s behavior.
method
is a language based on OO concepts that describes a set of diagrams and symbols used to graphically model a system.
UML (Unified Modeling Language)
Unified Modeling Language (UML)
Unified Modeling Language
UML
The term is used to refer to the task of creating a conceptual data model that could be implemented in any DBMS.
logical design
The is the representation of a database as “seen” by the DBMS.
internal model