BCIS 4620 DATABASE EXAM 1
The Crow's foot symbol with two vertical parallel lines indicates _____ cardinality.
(1,1)
Data warehouse routinely uses _____ structures in its complex, multilevel, multisource data environment.
2NF
From a structural point of view, 3NF is better than _____.
2NF
A table that is in 2NF and contains no transitive dependencies is said to be in _____.
3NF
A table where all attributes are dependent on the primary key but are independent of each other, and no row contains two or more multivalued facts about an entity is said to be in _____.
4NF
Some very specialized applications may require normalization beyond the _____.
4NF
_____ expresses the minimum and maximum number of entity occurrences associated with one occurrence of the related entity.
Cardinality
Of the following normal forms, _____ is mostly of theoretical interest.
DKNF
_____ databases reflect the ever-growing demand for greater scope and depth in the data on which decision support systems increasingly rely.
Data warehouse
A relationship is an association between _____. Correct!
Entities
The hierarchical model is software-independent.
False
_____ are especially useful when you are trying to determine what values in related tables cause referential integrity problems.
Outer joins
Depending on the sophistication of the application development software, nulls can create problems when functions such as COUNT, AVERAGE, and SUM are used.
True
The relationships depicted within the specialization hierarchy are sometimes described in terms of "is-a" relationships.
True
The row's range of permissible values is known as its domain.
True
To implement a small database, a database designer must know the "1" and the "M" sides of each relationship and whether the relationships are mandatory or optional.
True
A partial completeness constraint is represented by _____.
a single horizontal line under a circle
Improving _____ leads to more flexible queries.
atomicity
To simplify the conceptual design, most higher-order relationships are decomposed into appropriate equivalent _____ relationships whenever possible.
binary
Another name for a composite entity is a(n) _____ entity.
bridge
The first step in building an entity-relationship diagram (ERD) is _____.
creating a detailed narrative of the organization's description of operations
Knowing the minimum and maximum number of _____ occurrences is very helpful at the application software level.!
entity
In organizations that generate large number of transactions, _____ are often a top priority in database design.
high processing speeds
Referential _____ dictates that the foreign key must contain values that match the primary key in the related table, or must contain null.Correct!
integrity
A table is in 4NF if it is in 3NF, and _____.
it has no multivalued dependencies
According to Codd's _____ rule of relational databases, if the system supports low-level access to the data, users must not be allowed to bypass the integrity rules of the database.
nonsubversion
Overlapping subtypes are subtypes that contain _____ subsets of the supertype entity set.
nonunique
If an employee within an EMPLOYEE entity has a relationship with itself, that relationship is known as a _____ relationship.
recursive
A _____ key is defined as a key that is used strictly for data retrieval purposes.
secondary
A _____ attribute is one that cannot be subdivided.
simple
The _____ depicts the arrangement of higher-level entity supertypes (parent entities) and lower-level entity subtypes (child entities).
specialization hierarchy
A _____ entity has a primary key that is partially or totally derived from the parent entity in the relationship.
weak
In the entity relationship diagram (ERD), cardinality is indicated using the _____ notation, where max is the maximum number of associated entities and min represents the minimum number of associated entities.
(min, max)
To generate a surrogate key, Microsoft Access uses a(n) _____ data type.
AutoNumber
Data stored at their highest level of granularity are said to be atomic data.
False
Dependencies that are based on only a part of a composite primary key are called transitive dependencies.
False
Disjoint subtypes are subtypes that contain nonunique subsets of the supertype entity set.
False
In Chen notation, there is no way to represent cardinality.
False
_____ is the bottom-up process of identifying a higher-level, more generic entity supertype from lower-level entity subtypes.
Generalization
The entity relationship model uses the associative entity to represent a(n) _____ relationship between two or more entities.
M:N
The _____ constraint can be placed on a column to ensure that every row in the table has a value for that column.
NOT NULL
_____, also known as RESTRICT, yields values for all rows found in a table that satisfy a given condition.
SELECT
Which of the following is a specialization hierarchy disjoint constraint scenario in case of partial completeness?
Subtype discriminator can be null.
Which of the following is a specialization hierarchy overlapping constraint scenario in case of partial completeness?
Supertype has optional subtypes.
When the specific cardinalities are not included on the diagram in Crow's Foot notation, cardinality is implied by the use of _____.
Symbols
A composite identifier is a primary key composed of more than one attribute.
True
A data dictionary is sometimes described as "the database designer's database" because it records the design decisions about tables and their structures.
True
A design trap occurs when a relationship is improperly or incompletely identified and is therefore represented in a way that is not consistent with the real world.
True
Denormalization produces a lower normal form.
True
In the context of partial dependencies, data redundancies occur because every row entry requires duplication of data.
True
An entity cluster is formed by combining multiple interrelated entities into _____.
a single abstract entity object
An atomic attribute _____.
cannot be further subdivided
The purpose of an entity _____ is to simplify an entity-relationship diagram (ERD) and thus enhance its readability.
cluster
Each table _____ represents an attribute.
column
A(n) _____ is an orderly arrangement used to logically access rows in a table.
index
Complex _____ requirements may dictate data transformations, and they may expand the number of entities and attributes within the design.
information
The property of _____ enables an entity subtype to inherit the attributes and relationships of the supertype.
inheritance
A(n) _____ only returns matched records from the tables that are being joined.
inner join
Database design is a(n) _____ process based on repetition.
iterative
In the relational model, _____ are important because they are used to ensure that each row in a table is uniquely identifiable.
keys
A _____ is any key that uniquely identifies each row.
superkey
A _____ relationship exists when three entities are associated.
ternary
A _____ relationship exists when an association is maintained within a single entity.
unary
At the implementation level, the supertype and its subtype(s) depicted in a specialization hierarchy maintain a(n) _____ relationship.
1:1
The _____ relationship should be rare in any relational database design.!
1:1
The _____ relationship is the "relational model ideal."
1:M
A table that has all key attributes defined, has no repeating groups, and all its attributes are dependent on the primary key is said to be in _____.
1NF
From a structural point of view, 2NF is better than _____.
1NF
_____ are normally expressed in the form of rules.
Constraints
_____ serve as the intermediary between the user and the database.
DBMSs
A dependency of one nonprime attribute on another nonprime attribute is a partial dependency.
False
A subtype contains attributes that are common to all of its supertypes.
False
A table is in BCNF if every determinant in the table is a foreign key.
False
A weak relationship exists if the primary key of the related entity contains at least one primary key component of the parent entity.
False
Character data can contain any character or symbol intended for mathematical manipulation.
False
Composite attributes make it easier to facilitate detailed queries.
False
Entity subtypes do not inherit the relationships in which the supertype entity participates.
False
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
In a natural join, the column on which the join was made occurs twice in the new table.
False
In an SQL-based relational database, each table is dependent on every other table.
False
In implementation terms, an entity is existence-dependent if it has a mandatory primary key.
False
In specialization hierarchies with multiple levels of supertype and subtypes, a lower-level subtype can inherit only a few of the attributes and relationships from its upper-level supertypes.
False
Normalization is a process that is used for changing attributes to entities.
False
Normalization purity is often easy to sustain in the modern database environment.
False
One advantage of a database system over previous data management approaches is that the database system is considerably less complex.
False
Only a single attribute, not multiple attributes, can define functional dependence.Correct!
False
Overlapping subtypes are subtypes that contain a unique subset of the supertype entity set.
False
Referential integrity and participation are both bidirectional, meaning that they must be addressed in both directions along a relationship.
False
Relationships between entities always operate in one direction.
False
Software vendors have adopted the Chen representation because of its compact representation.
False
The Crow's Foot notation easily identifies multivalued attributes.
False
The Crow's Foot notation is less implementation-oriented than the Chen notation.
False
The DBMS reveals much of the database's internal complexity to the application programs and users.
False
The SELECT operator yields a vertical subset of a table. Correct!
False
The entity relationship model (ERM) is dependent on the database type.
False
The existence of a mandatory relationship indicates that the minimum cardinality is 0 or 1 for the mandatory entity.
False
The external model is the representation of the database as "seen" by the DBMS.
False
The function of the primary key is to describe an entity.
False
The idea of determination is unique to the database environment.
False
The one-to-many (1:M) relationship is easily implemented in the relational model by putting the foreign key of the "1" side in the table of the "many" side as a primary key.
False
The order of the rows and columns is important to the DBMS.
False
The property of a subtype discriminator enables an entity supertype to inherit the attributes and relationships of the subtype.
False
To model time-variant data, one must create a new entity in an M:N relationship with the original entity.
False
True
False
When data are entered into a form and saved, they are placed in the underlying database as knowledge.
False
Within a specialization hierarchy, a supertype can exist only within the context of a subtype.
False
Date attributes contain calendar dates stored in a special format known as the _____ date format.
Julian
Composite primary keys are particularly useful as identifiers of composite entities, where each primary key combination is allowed only once in the _____ relationship.
M:N
The conceptual model can handle _____ relationships and multivalued attributes.
M:N
_____ relationships can be implemented by creating a new entity in 1:M relationships with the original entities.
M:N
_____ returns only the attributes requested, in the order in which they are requested.
PROJECT
_____ relates to the activities that make the database execute transactions more efficiently in terms of storage and access speed.
Performance tuning
_____ logic, used extensively in mathematics, provides a framework in which an assertion (statement of fact) can be verified as either true or false.
Predicate
To be considered minimally relational, the DBMS must support the key relational operators _____, PROJECT, and JOIN.
SELECT
_____ are the result of formatting disorganized data in order to facilitate storage, use and generation of information.
Structured data
A null is created when you press the Enter key or the Tab key to move to the next entry without making a prior entry of any kind.
True
A table is in fourth normal form if it is in third normal form and has no independent multivalued dependencies.
True
A weak entity has a primary key that is partially or totally derived from the parent entity in the relationship.
True
All relational tables satisfy the 1NF requirements.
True
An entity cluster is a "virtual" entity type used to represent multiple entities and relationships in the ERD.
True
An entity in the entity relationship model corresponds to a table in the relational environment.
True
An entity supertype can have disjoint or overlapping entity subtypes.
True
As rare as 1:1 relationships should be, certain conditions absolutely require their use.
True
At the implementation level, the supertype and its subtype(s) depicted in the specialization hierarchy maintain a 1:1 relationship.
True
Connectivities and cardinalities are established by concise statements known as business rules.
True
Dependency diagrams are very helpful in getting a bird's-eye view of all the relationships among a table's attributes.
True
Each table in a relational database must have a primary key. Correct!
True
Entity supertypes and subtypes are organized in a specialization hierarchy.
True
If the attribute (B) is functionally dependent on a composite key (A) but not on any subset of that composite key, the attribute (B) is fully functionally dependent on (A).
True
Implementing overlapping subtypes requires the use of one discriminator attribute for each subtype.
True
In a 1:M relationship, to avoid the possibility of referential integrity errors, the data of the "1" side must be loaded first.
True
In order to meet performance requirements, portions of the database design may need to be occasionally denormalized.
True
In the Chen and Crow's Foot notations, an entity is represented with a rectangle containing the entity's name.
True
In the entity relationship model, a table row corresponds to an entity instance.
True
In the original Chen notation, each attribute is represented by an oval with the attribute name connected to an entity rectangle with a line.
True
It is possible for a table in 2NF to exhibit transitive dependency, where the primary key may rely on one or more nonprime attributes to functionally determine other nonprime attributes.
True
Normalization represents a micro view of the entities within the ERD.
True
Normalization works through a series of stages called normal forms.
True
One important inheritance characteristic is that all entity subtypes inherit their primary key attribute from their supertype.
True
RDBMSs enforce integrity rules automatically.
True
Relational algebra defines the theoretical way of manipulating table contents using relational operators.
True
Relational models view data as part of a table or collection of tables in which all key values must be identified.
True
Repeating groups must be eliminated by ensuring that each row defines a single entity.
True
Since a partial dependency can exist only if a table's primary key is composed of several attributes, if a table in 1NF has a single-attribute primary key, then the table is automatically in 2NF.
True
Specialization is the top-down process of identifying lower-level, more specific entity subtypes from a higher-level entity supertype.
True
The DIFFERENCE operator subtracts one table from the other.
True
The DIVIDE operation uses one single-column table (e.g., column "a") as the divisor and one two-column table (e.g., columns "a" and "b") as the dividend.
True
The combination of normalization and ER modeling yields a useful ERD, whose entities can be translated into appropriate table structures.
True
The completeness constraint can be partial or total.
True
The entity supertype contains common characteristics, and the entity subtypes each contain their own unique characteristics.
True
The objective of normalization is to ensure that each table conforms to the concept of well-formed relations.
True
The practical significance of taking the logical view of a database is that it serves as a reminder of the simple file concept of data storage.
True
You can think of a table as a persistent representation of a logical relation.
True
The _____ notation of entity-relationship modelling can be used for both conceptual and implementation modelling.
UML
Oracle 12c, MS SQL Server, and Tamino are examples of _____ data models.
XML Hybrid
A _____ key can be described as a minimal superkey, a superkey without any unnecessary attributes.
candidate
BCNF can be violated only if the table contains more than one _____ key.
candidate
A _____ attribute can be further subdivided to yield additional attributes.
composite
The entity relationship diagram (ERD) represents the _____ database as viewed by the end user.
conceptual
A derived attribute is indicated in the Chen notation by a _____ that connects the attribute and an entity.
dashed line
A(n) _______ enables a database administrator to describe schema components.
data definition language (DDL)
A _____ contains at least all of the attribute names and characteristics for each table in the system.
data dictionary
In a(n) _____ diagram, the arrows above the attributes indicate all desirable dependencies.
dependency
From a system functionality point of view, _____ attribute values can be calculated when they are needed to write reports or invoices.
derived
The decision to store _____ attributes in database tables depends on the processing requirements and the constraints placed on a particular application.
derived
Attribute A _____ attribute B if all of the rows in the table that agree in value for attribute A also agree in value for attribute B.
determines
In the context of total completeness, in a(n) _____, every supertype occurrence is a member of only one subtype.
disjoint constraint
A(n) _____ is the set of possible values for a given attribute.
domain
A total completeness constraint is represented by a _____.
double horizontal line under a circle
The extended entity relationship model (EERM) is sometimes referred to as the _____.
enhanced entity relationship model
The CUSTOMER table's primary key is CUS_CODE. The CUSTOMER primary key column has no null entries, and all entries are unique. This is an example of _____ integrity.Correct!
entity
A(n)_____ is a generic entity type that is related to one or more entity subtypes.
entity supertype
The default comparison condition for the subtype discriminator attribute is the _____ comparison.
equality
An entity is said to be _____-dependent if it can exist in the database only when it is associated with another related entity occurrence.
existence
In a real-world environment, we must strike a balance between design integrity and _____.
flexibility
A _____ is the primary key of one table that has been placed into another table to create a common attribute.
foreign key
In a database context, the word _____ indicates the use of the same attribute name to label different attributes.
homonym
According to Codd's _____ rule of relational databases, application programs and ad hoc facilities are logically unaffected when changes are made to the table structures that preserve the original table values (changing order of columns or inserting columns).
logical data independence
A specialization hierarchy can have _____ level(s) of supertype/subtype relationships.
many
In a _____ situation, one key determines multiple values of two other attributes and those attributes are independent of each other.
multivalued dependency
A _____ key is a real-world, generally accepted identifier used to uniquely identify real-world objects.
natural
A(n) _____ join links tables by selecting only the rows with common values in their common attribute(s).
natural
If one exists, a data modeler uses a _____ as the primary key of the entity being modeled.
natural identifier
The "_____" characteristic of a primary key states that the primary key should not have embedded semantic meaning.
nonintelligent
The most likely data type for a surrogate key is _____.
numeric
Ideally, an entity identifier is composed of _____ attribute(s).
one
Within a specialization hierarchy, every subtype can have _____ supertype(s) to which it is directly related.
only one
The existence of a(n) _____ entity indicates that its minimum cardinality is zero.
optional
If Tiny College has some departments that are classified as "research only" and do not offer courses, the COURSE entity of the college database would be _____ the DEPARTMENT entity.
optional to
In the context of total completeness, in a(n) _____, every supertype occurrence is a member of at least one subtype.
overlapping constraint
Dependencies based on only a part of a composite primary key are known as _____ dependencies.
partial
If a table has multiple candidate keys and one of those candidate keys is a composite key, the table can have _____ based on this composite candidate key even when the primary key chosen is a single attribute.
partial dependencies
One important inheritance characteristic is that all entity subtypes inherit their _____ key attribute from their supertype.
primary
The most important characteristic of an entity is its _____ key, used to uniquely identify each entity instance.
primary
An attribute that is part of a key is known as a(n) _____ attribute.
prime
A _____ derives its name from the fact that a collection of multiple entries of the same type can exist for any single key attribute occurrence.
repeating group
A relational table must not contain a(n) _____.
repeating group
The "_____" characteristic of a primary key states that the selected primary key must not be composed of any attribute(s) that might be considered a violation.
security-compliant
According to the "preferably single-attribute" characteristic of a primary key, the primary key:
should have the minimum number of attributes possible.
When using the Crow's Foot notation, the associative entity is indicated by _____ relationship lines between the parents and the associative entity.Correct!
solid
If an entity can exist apart from all of its related entities, then it is existence-independent, and it is referred to as a(n) _____ entity.
strong
A(n) _____ is the attribute in the supertype entity that determines to which entity subtype each supertype occurrence is related.
subtype discriminator
A _____ is a primary key created by a database designer to simplify the identification of entity instances.
surrogate key
In a database context, a(n) _____ indicates the use of different names to describe the same attribute.
synonym
The _____ is actually a system-created database whose tables store the user/designer-created database characteristics and contents.
system catalog
An example of denormalization is using a _____ denormalized table to hold report data. This is required when creating a tabular report in which the columns represent data that are stored in the table as rows.
temporary
When a table contains only one candidate key, _____ are considered to be equivalent.
the 3NF and the BCNF
Granularity refers to _____.
the level of detail represented by the values in a table's row
Normalization works through a series of stages called normal forms. For most purposes in business database design, _____ stages are as high as you need to go in the normalization process.
three
A(n) _____ exists when there are functional dependencies such that Y is functionally dependent on X, Z is functionally dependent on Y, and X is the primary key.
transitive dependency
When two or more tables share the same number of columns, and when their corresponding columns share the same or compatible domains, they are said to be _____.
union-compatible
Nonoverlapping subtypes are subtypes that contain a(n) _____ subset of the supertype entity set.
unique
When you define a table's primary key, the DBMS automatically creates a(n) _____ index on the primary key column(s) you declared.
unique
The "_____" characteristic of a primary key states that the primary key must uniquely identify each entity instance, must be able to guarantee unique values, and must not contain nulls.
unique values
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
A disadvantage of the relational database management system (RDBMS) is its inability to hide the complexities of the relational model from the user.
False
An advantage of database systems is that you needn't perform frequent updates and apply latest patches.
False
Data and information are essentially the same thing.
False
Database programming languages receive all application requests and translate them into the complex operations required to fulfill those requests
False
Field refers to a collection of related records.
False
One disadvantage of the DBMS is that it increases the risk of data security breaches.
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
The relational model is hardware-dependent and software-independent.
False
_____ is the result of revealing the meaning of raw facts.
Information
Which of the following is true of business rules?
They can serve as a communication tool between the users and designers.
Which of the following is true of spreadsheet applications?
They enhance the user's ability to understand the data.
Data constitute the building blocks of information.
True
M:N relationships are not appropriate in a relational model.
True
_____ 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.
Unstructured
A(n) _____ might be written by a programmer or it might be created through a DBMS utility program.
application
A(n) _____ is the equivalent of a field in a file system.
attribute
The database structure in a DBMS is stored as a _____.
collection of files
A(n) _____ is a restriction placed on the data.
constraint
A noun in a business rule translates to a(n) _____ in the data model.
entity
A(n) _____ is anything about which data are to be collected and stored.
entity
A(n) _____ represents a particular type of object in the real world.
entity
The _____ model uses the term connectivity to label the relationship types.
entity relationship
A _____ is a character or group of characters that has a specific meaning.
field
A _____ is a collection of related records.
file
VMS/VSAM is an example of the _____.
file system data model
Accurate, relevant, and timely information is the key to ____.
good decision making
In the _____ model, the basic logical structure is represented as an upside-down tree.
hierarchical
The _____ data model is said to be a semantic data model.
object-oriented
A _____ is a logically connected set of one or more fields that describes a person, place, or thing.
record
The hierarchical data model was developed in the _____.
1960s
Corporations use only structured data.
False
In Chen notation, entities and relationships have to be oriented horizontally; not vertically.
False
_____ is the body of information and facts about a specific subject.
Knowledge
Which of the following is true of NoSQL databases?
They are not based on the relational model.
A data model is usually graphical.
True
An implementation-ready data model should contain a description of the data structure that will store the end-user data.
True
Business rules must be rendered in writing.
True
Structure is based on the type of processing to be performed on the data.
True
The network model has structural level dependence.
True
The only way to access the data in a database is through the DBMS.
True
Today, most relational database products can be classified as object/relational.
True
Within the database environment, a data model represents data structures with the purpose of supporting a specific problem domain.
True
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
The relational data model was developed in the _____.
1970s
The object-oriented data model was developed in the _____.
1980s
_____ exists when different versions of the same data appear in different places.
Data inconsistency
_____ 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
An operational database is sometimes referred to as an enterprise database.
False
Which of the following types of HDFS nodes acts as the interface between the user application and the HDFS?
Client node
Students and classes have a _____ relationship.
many-to-many
A(n) _____'s main function is to help one understand the complexities of the real-world environment.
model
Most data that can be encountered are best classified as _____.
semistructured
A desktop database is a _____ database
single-user
A(n) _____ database is used by an organization and supports many users across many departments.
enterprise
_____ are important because they help to ensure data integrity.
Constraints
_____ provide a description of the data characteristics and the set of relationships that link the data found within the database.
Metadata
A data warehouse can store data derived from many sources.
True
Data processing can be as simple as organizing data to reveal patterns.
True
A(n) _____ enables a database administrator to describe schema components.
data definition language (DDL)
The _____ model was developed to allow designers to use a graphical tool to examine structures rather than describing them with text.
entity relationship
In the _____ model, each parent can have many children, but each child has only one parent.
hierarchical
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 _____ data model uses the concept of inheritance.
object-oriented
A data warehouse contains historical data obtained from the _____.
operational databases
MySQL is an example of the _____.
relational data model
A verb associating two nouns in a business rule translates to a(n) _____ in the data model.
relationship
An implementation-ready data model needn't necessarily contain enforceable rules to guarantee the integrity of the data.
False
Business rules apply to businesses and government groups, but not to other types of organizations such as religious groups or research laboratories.
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
Data is the result of processing raw facts to reveal its meaning.
False
Database designers determine the data and information that yield the required understanding of the entire business.
False
Which of the following types of HDFS nodes stores all the metadata about a file system?
Name node
Each row in the relational table is known as an entity instance or entity occurrence in the ER model.
True
In an SQL-based relational database, rows in different tables are related based on common values in common attributes.
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
Metadata describe the data characteristics and the set of relationships that links the data found within the database.
True
One disadvantage of a database system over previous data management approaches is increased costs.
True
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
The organization of data within folders in a manual file system is determined by _______.
its expected use
The response of the DBMS to a query is the ___________
query result set
End-user data is _____.
raw facts of interest to the end user
A(n) _____ is bidirectional.
relationship
An XML database supports the storage and management of _____ XML data.
semistructured
Data is said to be verifiable if:
the data always yields consistent results.
