BCIS 4620 Exam 1

The relational data model was developed in the _____.

1970s

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

Client node

_____ are important because they help to ensure data integrity.

Constraints

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

DBMSs

_____ 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

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

Enterprise

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

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

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

False

Corporations use only structured data.

False

Data and information are essentially the same thing.

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

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

Field refers to a collection of related records.

False

In Chen notation, entities and relationships have to be oriented horizontally; not vertically.

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

One advantage of a database system over previous data management approaches is that the database system is considerably less complex.

False

One disadvantage of the DBMS is that it increases the risk of data security breaches.

False

Only a single attribute, not multiple attributes, can define functional dependence.

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 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.

False

The hierarchical model is software-independent.

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

False

When data are entered into a form and saved, they are placed in the underlying database as knowledge.

False

A _____ is a collection of related records.

File

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

Julian

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

Metadata

A workgroup database is a(n) _____ database.

Multiuser

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

Name node

_____ 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

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

Structured data

Which of the following is true of NoSQL databases?

They are not based on the relational model.

Which of the following is true of business rules?

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

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 data model is usually graphical.

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

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

True

Business rules must be rendered in writing.

True

Data constitute the building blocks of information.

True

Depending on the sophistication of the application development software, nulls can create problems when functions such as COUNT, AVERAGE, and SUM are used.

True

Each row in the relational table is known as an entity instance or entity occurrence in the ER model.

True

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

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

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

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

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

RDBMSs enforce integrity rules automatically.

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 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 only way to access the data in a database is through the DBMS.

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

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

True

You can think of a table as a persistent representation of a logical relation.

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

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

XML Hybrid

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

attribute

Each table _____ represents an attribute.

column

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

constraint

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 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

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.

entity relationship

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

field

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

its expected use

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

keys

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

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

A data warehouse contains historical data obtained from the _____.

operational databases

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

record

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

A(n) _____ is bidirectional.

relationship

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

Data is said to be verifiable if:

the data always yields consistent results.