Midterm Round 2

The Crow's foot symbol with two vertical parallel lines indicates _____ cardinality.

(1,1)

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)

The hierarchical data model was developed in the _____.

1960s

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

_____ expresses the minimum and maximum number of entity occurrences associated with one occurrence of the related entity.

Cardinality

_____ are important because they help to ensure data integrity.

Constraints

A(n) _______ enables a database administrator to describe schema components.

Data Definition Language (DDL)

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

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

Enterprise

The _____ model uses the term connectivity to label the relationship types.

Entity relationship

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

False

An operational database is sometimes referred to as an enterprise database.

False

Corporations use only structured data.

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

In Chen notation, there is no way to represent cardinality.

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

False

Referential integrity and participation are both bidirectional, meaning that they must be addressed in both directions along a relationship.

False

Software vendors have adopted the Chen representation because of its compact representation.

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 SELECT operator yields a vertical subset of a table.

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 row's range of permissible values is known as its domain.

False

Database design is a(n) _____ process based on repetition.

Iterative

Date attributes contain calendar dates stored in a special format known as the _____ date format.

Julian

_____ relationships can be implemented by creating a new entity in 1:M relationships with the original entities.

M:N

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

Metadata

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

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

Performance Tuning

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

Which of the following is true of spreadsheet applications?

They enhance the user's ability to understand the data

A composite identifier is a primary key composed of more than one attribute.

True

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 weak entity has a primary key that is partially or totally derived from the parent entity in the relationship.

True

An entity cluster is a "virtual" entity type used to represent multiple entities and relationships in the ERD.

True

Data constitute the building blocks of information.

True

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

True

Each table in a relational database must have a primary key.

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 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

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

True

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

True

RDBMSs enforce integrity rules automatically.

True

Structure is based on the type of processing to be performed on the data.

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

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

True

The _____ notation of entity-relationship modelling can be used for both conceptual and implementation modelling.

UML

A _____ relationship exists when an association is maintained within a single entity.

Unary

_____ data exist in the format in which they were collected.

Unstructured

A partial completeness constraint is represented by _____.

a single horizontal line under a circle

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

application

Which of the following types of HDFS nodes acts as the interface between the user application and the HDFS?

client node

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

constraint

The first step in building an entity-relationship diagram (ERD) is _____.

creating a detailed narrative of the organizations description of operations

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 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

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

entity

The _____ model was developed to allow designers to use a graphical tool to examine structures rather than describing them with text.

entity relationship

The default comparison condition for the subtype discriminator attribute is the _____ comparison.

equality

A subtype contains attributes that are common to all of its supertypes.

false

Character data can contain any character or symbol intended for mathematical manipulation.

false

Entity subtypes do not inherit the relationships in which the supertype entity participates.

false

Overlapping subtypes are subtypes that contain a unique subset of the supertype entity set.

false

The function of the primary key is to describe an entity.

false

The hierarchical model is software-independent.

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

Within a specialization hierarchy, a supertype can exist only within the context of a subtype.

false

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

field

VMS/VSAM is an example of the _____.

fil system data model

In organizations that generate large number of transactions, _____ are often a top priority in database design.

high processing speeds

Complex _____ requirements may dictate data transformations, and they may expand the number of entities and attributes within the design.

information

_____ is the result of revealing the meaning of raw facts.

information

The property of _____ enables an entity subtype to inherit the attributes and relationships of the supertype.

inheritance

Referential _____ dictates that the foreign key must contain values that match the primary key in the related table, or must contain null.

integrity

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

its expected use

A specialization hierarchy can have _____ level(s) of supertype/subtype relationships.

many

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 "_____" characteristic of a primary key states that the primary key should not have embedded semantic meaning.

nonintelligent

Overlapping subtypes are subtypes that contain _____ subsets of the supertype entity set.

nonunique

The _____ data model is said to be a semantic data model.

object-oriented

The existence of a(n) _____ entity indicates that its minimum cardinality is zero.

optional

_____ are especially useful when you are trying to determine what values in related tables cause referential integrity problems.

outer joins

In the context of total completeness, in a(n) _____, every supertype occurrence is a member of at least one subtype.

overlapping constraint

The most important characteristic of an entity is its _____ key, used to uniquely identify each entity instance.

primary

A _____ key is defined as a key that is used strictly for data retrieval purposes.

secondary

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

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

semistructured

Most data that can be encountered are best classified as _____.

semistructured

A desktop database is a _____ database.

single-user

The _____ depicts the arrangement of higher-level entity supertypes (parent entities) and lower-level entity subtypes (child entities).

specialization hierarchy

A _____ is any key that uniquely identifies each row.

superkey

In a database context, a(n) _____ indicates the use of different names to describe the same attribute.

synonym

A data model is usually graphical.

true

One important inheritance characteristic is that all entity subtypes inherit their primary key attribute from their supertype.

true

Relational algebra defines the theoretical way of manipulating table contents using relational operators.

true

The DIFFERENCE operator subtracts one table from the other.

true

The entity supertype contains common characteristics, and the entity subtypes each contain their own unique characteristics.

true

The network model has structural level dependence.

true

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

true

Nonoverlapping subtypes are subtypes that contain a(n) _____ subset of the supertype entity set.

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

A _____ entity has a primary key that is partially or totally derived from the parent entity in the relationship.

weak

The _____ constraint can be placed on a column to ensure that every row in the table has a value for that column.

NOT NULL

Which of the following types of HDFS nodes stores all the metadata about a file system?

Name node

In an SQL-based relational database, rows in different tables are related based on common values in common attributes.

True

_____ are normally expressed in the form of rules.

constraints

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

entity

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.

entity

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

false

In a natural join, the column on which the join was made occurs twice in the new table.

false

In implementation terms, an entity is existence-dependent if it has a mandatory primary key.

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

A _____ is the primary key of one table that has been placed into another table to create a common attribute.

foreign key

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

good decision making

In the relational model, _____ are important because they are used to ensure that each row in a table is uniquely identifiable.

keys

MySQL is an example of the _____.

relational data model

As rare as 1:1 relationships should be, certain conditions absolutely require their use.

true