Secondaryin the entity relationship diagram erd

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

unique

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

Relationships between entities always operate in one direction. False

Mathematical operators cannot be used to place restrictions on character-based attributes. false

Each table _______ represents an attribute.
column

A relationship is an association between _______.
entities

RDBMSs enforce integrity rules automatically.
true

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

foreign key

A _______ is any key that uniquely identifies each row.
superkey

keys

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

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

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

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

Integrity

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

True

A weak relationship exists if the primary key of the related entity contains at least one primary key component of the parent entity.

False

The Crow's Foot notation is less implementation-oriented than the Chen notation.

False

solid

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

Unary relationships are common in manufacturing industries. True

Relationships between entities always operate in one direction. False

In a 1:M relationship, to avoid the possibility of referential integrity errors, the data of the "1" side must be loaded first.

True

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

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

existence

The Crow's Foot notation easily identifies multivalued attributes. False

A _____ attribute is one that cannot be subdivided.
simple

The decision to store _____ attributes in database tables depends on the processing requirements and the constraints placed on a particular application.

To simplify the conceptual design, most higher-order relationships are decomposed into appropriate equivalent _____ relationships whenever possible.

binary

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)

True

The entity relationship diagram (ERD) represents the _____ database as viewed by the end user. = conceptual2.A(n) _____ is the set of possible values for a given attribute. = domain3.Ideally, an entity identifier is composed of _____ attribute(s). = one4.A _____ attribute can be further subdivided to yield additional attributes. = composite5.A _____ attribute is one that cannot be subdivided. = simple6.The conceptual model can handle _____ relationships and multivalued attributes. = M:N7.The decision to store _____ attributes in database tables depends on the processing
requirements and the constraints placed on a particular application. = derived8.A relationship is an association between _____. = entities9._____ expresses the minimum and maximum number of entity occurrences associated with one occurrence of the related entity. = Cardinality10.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)11.

a _____ attribute need not be physically stored within the database derived

a relationship _____ is difficult to establish if only one side of the relationship is known classification

a weak entity must be _____-dependent

existence

a relationship _____ indicates the # of entities or participants associated with a relationship degree

an _____ process is based on repetition of processes and procedures iterative

the traditional SDLC phases are _____, analysis, detailed systems design, implementation, and maintenance
planning

an initial assessment of the information flow-and-extent requirements must be made during the _____ portion of the SDLC
planning

audit trails

the _____ describes the general conditions in which a company operates, its organization structure, and its mission
company situation

_____ allow end users to access the database w/o being able to download the information from their workstations
diskless workstations

_____ allows the assignment of access rights to specific authorized users password security

a _____ rule is a brief and precise narrative of a policy, procedure, or principle within a specific organization's environment
business

because real-world database design is generally done by teams, the database design is probably divided into major components known as _____
modules

the term _____ describes the strength of the relationships found among a module's entities cohesivity

when selecting DMBS _____, items to consider include processors, RAM, and disk space hardware

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.

True
False
False

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

Equijoins
Inner joins
Theta joins
Outer joins
Outer joins

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
False
True

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

True
False
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
False
True

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

True
False
False

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

DIFFERENCE
UNION
PROJECT
SELECT
PROJECT

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

True
False
True

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

homonym
entity
synonym
dupicate
synonym

select-compatible
union-capatible
intersect-compatible
union-compatible

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

SELECT
DIFFERENCE
INTERSECT
UNION
SELECT

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

uniqueness
attribute
integrity
model
integrity

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

True
False
False

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

True
False
True

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

indexes
relations
logical structures
keys
keys

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

foreign
attribute
natural
unique
natural

The DIFFERENCE operator subtracts one table from the other.

A ____ key is a key that consists of more than one attribute. A. primary C. composite B. foreign D. domain ANS: C

____ attributes can have several values. A. Composite C. Single-valued B. Simple D. Multivalued ANS: D

Cardinality expresses the specific number of entity occurrences associated with every occurrence of a related entity.

False

Derived attributes are stored in a special database table. False

Cardinality expresses the specific number of entity occurrences associated with one occurrence of the related entity.

The ER diagram represents the conceptual database as viewed by the end user. True

The word "entity" in the ER model corresponds to a table. True

Cardinality

The existence of a mandatory relationship indicates that the minimum cardinality is 1 for the mandatory entity.

True

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

The idea of determination is unique to the database environment. False

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

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 DIFFERENCE operator subtracts one table from the other. True

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

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

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

foreign key

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

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

NOT NULL

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

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 _____.

Outer joins

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

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

The _____ relationship is the "relational model ideal."
1:M

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

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

non-subversion

A table is also called a(n) _____ because the relational model's creator, E. F. Codd, used the two terms as synonyms
relation

The relational operators have the property of _____; that is, the use of relational algebra operators on existing relations (tables) produces new relations
closure

PRODUCT yields all possible pairs of rows from two tables, also known as the _____ product. Cartesian

data dictionary

The _____ catalog can be described as a detailed system data dictionary that describes all objects within the database, including data about table names, the table's creator and creation date, the number of columns in each table, the data type corresponding to each column, index filenames, index creators, authorized users, and access privileges.