Exam Review Questions and A Level Marking
Scheme Latest 2024/2025
inheritance - correct answer In the object-oriented data model, the ability of an object
to inherit the data structure and methods of the classes above it in the class hierarchy.
internal model - correct answer In database modeling, a level of data abstraction that
adapts the conceptual model to a specific DBMS model for implementation. The internal
model is the representation of a database as "seen" by the DBMS. In other words, the
internal model requires a designer to match the conceptual model's characteristics and
constraints to those of the selected implementation model.
internal schema - correct answer A representation of an internal model using the
database constructs supported by the chosen database
internet - correct answer A global network of computers connected together through a
standard network protocol know as Transmission Control Protocol/Internet Protocol
(TCP/IP) You can think of the internet as the "highway" on which the data travel.
key-value - correct answer A data model based on a structure composed of two data
elements: a key and a value, in which every key has a corresponding value or set of
values. The _____ is also called the associative or attribute-value data model.
many-to-many (M:N or *..*) relationship - correct answer Association among two or
more entities in which one occurrence of an entity is associated with many occurances
of a related entity and one occurrence of the related entity is associated with many
occurrences of the first entity.
MapReduce - correct answer An open-source application programming interface (API)
that provides fast data analytics services; one of the main Big Data technologies that
allows organizations to process massive data stores.
,method - correct answer In the object-oriented data model, a named set of instructions
to perform an action. ____ represtent real-world actions, and are invoked through
messages.
name node - correct answer One of three types of nodes used in the Hadoop
Distributed File System (HDFS). The data node stores all metadata about the file
system.
network model - correct answer An early data model that represented data as a
collection of record types in 1:M relationships.
object - correct answer An abstract representation of a real world entity that has a
unique identity, embedded properties and the ability to interact with other objects and
itself.
object-oriented data model (OODM) - correct answer A data model whose basic
modeling structure is an object.
object-oriented database management system (OODBMS) - correct answer Data
Management software used to manage date in an object-oriented database model.
object/relational database management system (O/R DBMS) - correct answer A DBMS
based on the extended relational model (ERDM). The ERDM, championed by many
relational database researchers, constitutes the relational model's response to the
OODM. This model includes many of the object-oriented model's best features within an
inherently simpler relational database structure.
one-to-many (1:M or 1..*) relationship - correct answer Associations among two or
more entities that are used by data models. In a 1:M relationship, one entity instance is
associated with many instances of the related entity.
one-to-one (1:1 or 1..1) relationship - correct answer Associations among two or more
entities that are used by data models. In a 1:1 relationship, one entity instance is
associated with onlly one instance of the related entity,
, relation - correct answer A logical construct perceived to be a two dimensional
structure composed of intersecting rows (entities) and columns(attributes) that
represents an entity set in the relational model.
relational database management system (RDBMS) - correct answer A collection of
programs that manages a relational database. The RDBMS software translates a user's
logical requests (quieries) into commands that physically locate and retrieve the
requested data.
relational diagram - correct answer A graphical representation of a relational
database's entities, the attributes within those entities, and the relationships among the
entities.
relational model - correct answer Developed by E.F. Codd of IBM in 1970, the
relational model is based on mathmatical set theory and represtents data as
independent relations. Each relation (table) is conceptually represented as a two
dimensional structure of intersectin rows and columns. The relations are related to each
other throufht the sharing of common entity characteristics (values in columns).
relationship - correct answer an association between entities.
schema - correct answer A logical grouping of database objects, such as tables,
indexes, views, and queries, that are related to each other. Usually, a schema belongs
to a single user application.
segment (SEGM) - correct answer in the hierarchical data model, the equivalent of a
file system's record type.
subschema - correct answer The portion of the database that interacts with the
application programs.
superclass - correct answer In a class hierarchy, the ________ is the more general
classification from which the subclasses inherit data structures and behaviors.