CS6400 - Exam Study Guide Questions Solved 100%
Correct | Verified Answers
active database systems - ✔✔provide active rules that can automatically initiate actions
when certain events and conditions occur
Implications of Using the Database Approach - ✔✔-Potential for Enforcing Standards
-Reduced Application Development Time
-Flexibility
-Availability of Up-to-Date Information
-Economies of Scale
Extending Database Capabilities for New Applications - ✔✔-Scientific applications that store
large amounts of data resulting from scientific experiments
-Storage and retrieval of images
-Storage and retrieval of videos
-Data mining applications that analyze large amounts of data
-Spatial applications that store and analyze spatial locations of data
-Time series applications that store information such as economic data at regular points in time,
When Not to Use a DBMS - ✔✔-High initial investment in hardware, software, and training
-The generality that a DBMS provides for defining and processing data
-Overhead for providing security, concurrency control, recovery, and integrity functions
server module - ✔✔typically handles data storage, access, search, and other functions
,client module - ✔✔Typically, application programs and user interfaces that access the
database run in the client module
Data Abstraction - ✔✔suppression of details of data organization and storage, and the
highlighting of the essential features for an improved understanding of data
data model - ✔✔a collection of concepts that can be used to describe the structure of a
database—provides the necessary means to achieve this abstraction
structure of database - ✔✔Data types, relationships and constraints
High-level or conceptual data models - ✔✔provide concepts that are close to the way many
users perceive data
Low-level or physical data models - ✔✔describe the details of how data is stored on
computer storage media
representational data models - ✔✔provide concepts that may be easily understood by end
users but that are not too far removed from the way data is organized in computer storage
entity - ✔✔represents a real-world object or concept, such as an employee or a project from
the miniworld that is described in the database
attribute - ✔✔represents some property of interest that further describes an entity, such as
the employee's name or salary.
relationship - ✔✔represents an association among the entities, for example, a works-on
relationship between an employee and a project.
, entity-relationship model - ✔✔a popular high-level conceptual data model
Database Schema - ✔✔a "map" of data tables and their relationships to one another
Schema Diagram - ✔✔a displayed schema
Database state or snapshot - ✔✔Data in database at a particular moment in time
valid state - ✔✔a state that satisfies the structure and constraints specified in the schema
Schema Evolution - ✔✔Changes applied to schema as application requirements change
intension - ✔✔The schema is sometimes called
extension - ✔✔a database state is called an _________ of the schema
Conceptual Schema - ✔✔describes the structure of the whole database for a community of
users. The conceptual schema hides the details of physical storage structures and concentrates
on describing entities, data types, relationships, user operations, and constraints
internal schema - ✔✔describes the physical storage structure of the database. It uses a
physical data model and describes the complete details of data storage and access paths for the
database.
external schema - ✔✔describes the part of the database that a particular user group is
interested in and hides the rest of the database from that user group. It is typically
implemented using a representational data model, possibly based on an external schema
design in a high-level conceptual data model
Correct | Verified Answers
active database systems - ✔✔provide active rules that can automatically initiate actions
when certain events and conditions occur
Implications of Using the Database Approach - ✔✔-Potential for Enforcing Standards
-Reduced Application Development Time
-Flexibility
-Availability of Up-to-Date Information
-Economies of Scale
Extending Database Capabilities for New Applications - ✔✔-Scientific applications that store
large amounts of data resulting from scientific experiments
-Storage and retrieval of images
-Storage and retrieval of videos
-Data mining applications that analyze large amounts of data
-Spatial applications that store and analyze spatial locations of data
-Time series applications that store information such as economic data at regular points in time,
When Not to Use a DBMS - ✔✔-High initial investment in hardware, software, and training
-The generality that a DBMS provides for defining and processing data
-Overhead for providing security, concurrency control, recovery, and integrity functions
server module - ✔✔typically handles data storage, access, search, and other functions
,client module - ✔✔Typically, application programs and user interfaces that access the
database run in the client module
Data Abstraction - ✔✔suppression of details of data organization and storage, and the
highlighting of the essential features for an improved understanding of data
data model - ✔✔a collection of concepts that can be used to describe the structure of a
database—provides the necessary means to achieve this abstraction
structure of database - ✔✔Data types, relationships and constraints
High-level or conceptual data models - ✔✔provide concepts that are close to the way many
users perceive data
Low-level or physical data models - ✔✔describe the details of how data is stored on
computer storage media
representational data models - ✔✔provide concepts that may be easily understood by end
users but that are not too far removed from the way data is organized in computer storage
entity - ✔✔represents a real-world object or concept, such as an employee or a project from
the miniworld that is described in the database
attribute - ✔✔represents some property of interest that further describes an entity, such as
the employee's name or salary.
relationship - ✔✔represents an association among the entities, for example, a works-on
relationship between an employee and a project.
, entity-relationship model - ✔✔a popular high-level conceptual data model
Database Schema - ✔✔a "map" of data tables and their relationships to one another
Schema Diagram - ✔✔a displayed schema
Database state or snapshot - ✔✔Data in database at a particular moment in time
valid state - ✔✔a state that satisfies the structure and constraints specified in the schema
Schema Evolution - ✔✔Changes applied to schema as application requirements change
intension - ✔✔The schema is sometimes called
extension - ✔✔a database state is called an _________ of the schema
Conceptual Schema - ✔✔describes the structure of the whole database for a community of
users. The conceptual schema hides the details of physical storage structures and concentrates
on describing entities, data types, relationships, user operations, and constraints
internal schema - ✔✔describes the physical storage structure of the database. It uses a
physical data model and describes the complete details of data storage and access paths for the
database.
external schema - ✔✔describes the part of the database that a particular user group is
interested in and hides the rest of the database from that user group. It is typically
implemented using a representational data model, possibly based on an external schema
design in a high-level conceptual data model
