Database Midterm

simple

A _____ attribute is one that cannot be subdivided.

the data always yields consistent results.

Data is said to be verifiable if:

Julian

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

column

Each table _____ represents an attribute.

raw facts of interest to the end user

End-user data is _____.

data dictionary

A _____ contains at least all of the attribute names and characteristics for each table in the system.

field

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

file

A _____ is a collection of related records.

record

A _____ is a logically connected set of one or more fields that describes a person, place, or thing.

superkey

A _____ is any key that uniquely identifies each row.

foreign key

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

candidate

A _____ key can be described as a minimal superkey, a superkey without any unnecessary attributes.

secondary

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

operational databases

A data warehouse contains historical data obtained from the _____.

dashed line

A derived attribute is indicated in the Chen notation by a _____ that connects the attribute and an entity.

single-user

A desktop database is a _____ database.

entity

A noun in a business rule translates to a(n) _____ in the data model.

relationship

A verb associating two nouns in a business rule translates to a(n) _____ in the data model.

multiuser

A workgroup database is a(n) _____ database.

enterprise

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

workgroup

A(n) _____ database supports a relatively small number of users (usually fewer than 50) or a specific department within an organization.

data definition language (DDL)

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

constraint

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

index

A(n) _____ is an orderly arrangement used to logically access rows in a table.

entity

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

relationship

A(n) _____ is bidirectional.

attribute

A(n) _____ is the equivalent of a field in a file system.

natural

A(n) _____ join links tables by selecting only the rows with common values in their common attribute(s).

application

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

inner join

A(n) _____ only returns matched records from the tables that are being joined.

entity

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

model

A(n) _____'s main function is to help one understand the complexities of the real-world environment.

data definition language (DDL)

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

logical data independence

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).

nonsubversion

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.

good decision making

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

semistructured

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

bridge

Another name for a composite entity is a(n) _____ entity.

information

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

optional to

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.

recursive

If an employee within an EMPLOYEE entity has a relationship with itself, that relationship is known as a _____ relationship.

synonym

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

homonym

In a database context, the word _____ indicates the use of the same attribute name to label different attributes.

hierarchical

In the _____ model, each parent can have many children, but each child has only one parent.

hierarchical

In the _____ model, the basic logical structure is represented as an upside-down tree.

network

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.

keys

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

entity

Knowing the minimum and maximum number of _____ occurrences is very helpful at the application software level.

semistructured

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

relational data model

MySQL is an example of the _____.

XML Hybrid

Oracle 12c, MS SQL Server, and Tamino are examples of _____ data models.

integrity

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

many-to-many

Students and classes have a _____ relationship.

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.

NOT NULL

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

object-oriented

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

object-oriented

The _____ data model uses the concept of inheritance.

system catalog

The _____ is actually a system-created database whose tables store the user/designer-created database characteristics and contents.

entity relationship

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

entity relationship

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

1:M

The _____ relationship is the "relational model ideal."

1:1

The _____ relationship should be rare in any relational database design.

M:N

The conceptual model can handle _____ relationships and multivalued attributes.

collection of files

The database structure in a DBMS is stored as a _____.

M:N

The entity relationship model uses the associative entity to represent a(n) _____ relationship between two or more entities.

1960s

The hierarchical data model was developed in the _____.

1980s

The object-oriented data model was developed in the _____.

its expected use

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

1970s

The relational data model was developed in the _____.

query result set

The response of the DBMS to a query is the ___________

database system

The term _____ refers to an organization of components that define and regulate the collection, storage, management and use of data within a database environment.

SELECT

To be considered minimally relational, the DBMS must support the key relational operators _____, PROJECT, and JOIN.

file system data model

VMS/VSAM is an example of the _____.

symbols

When the specific cardinalities are not included on the diagram in Crow's Foot notation, cardinality is implied by the use of _____.

union-compatible

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 _____.

unique

When you define a table's primary key, the DBMS automatically creates a(n) _____ index on the primary key column(s) you declared.

They are not based on the relational model.

Which of the following is true of NoSQL databases?

They can serve as a communication tool between the users and designers.

Which of the following is true of business rules?

They enhance the user's ability to understand the data.

Which of the following is true of spreadsheet applications?

Data redundancy

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?

Client node

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

Name node

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

Outer joins

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

Constraints

_____ are important because they help to ensure data integrity.

Constraints

_____ are normally expressed in the form of rules.

Structured data

_____ are the result of formatting disorganized data in order to facilitate storage, use and generation of information.

Unstructured

_____ 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.

Data inconsistency

_____ exists when different versions of the same data appear in different places.

Cardinality

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

Data integrity

_____ is defined as the condition in which all of the data in the database are consistent with the real-world events and conditions.

Knowledge

_____ is the body of information and facts about a specific subject.

Information

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

Predicate

_____ logic, used extensively in mathematics, provides a framework in which an assertion (statement of fact) can be verified as either true or false.

Metadata

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

Performance tuning

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

M:N

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

PROJECT

_____ returns only the attributes requested, in the order in which they are requested.

DBMSs

_____ serve as the intermediary between the user and the database.

SELECT

_____, also known as RESTRICT, yields values for all rows found in a table that satisfy a given condition.