5698162
Pregunta 1
Pregunta
A circle across the relationship line near an entity indicates ________.
Respuesta
-
a maximum cardinality of "zero"
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a maximum cardinality of "one"
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a minimum cardinality of "optional"
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a minimum cardinality of "required"
Pregunta 2
Pregunta
A composite attribute is an attribute that ________.
Respuesta
-
Describes a characteristic of the relationship
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Is Multivalued
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Consists of a group of attributes
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Is calculated at run-time
Pregunta 3
Pregunta
A for-use-by pattern must involve what kind of entity?
Respuesta
-
Weak entity with one identifying relationship
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Strong entity
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Supertype entity
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Weak entity with two identifying relationships
Pregunta 4
Pregunta
A hash mark across the relationship line near an entity indicates ________.
Respuesta
-
A maximum cardinality of "zero"
-
A maximum cardinality of "one"
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A minimum cardinality of "optional"
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A minimum cardinality of "required"
Pregunta 5
Pregunta
A line-item pattern must involve what kind of entity?
Respuesta
-
Weak entity with one identifying relationship
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Weak entity with two identifying relationships
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Supertype entity
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Strong entity
Pregunta 6
Pregunta
A referential integrity constraint policy that insures that all rows containing a particular foreign key value in a table are eliminated from the table when the row containing the corresponding primary key value in a parent table is eliminated from the database is called ________.
Respuesta
-
Incremental updates
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Incremental deletes
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Cascading deletes
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Cascading updates
Pregunta 7
Pregunta
A referential integrity constraint policy that insures that foreign key values in a table are correctly maintained when there is a change to the primary key value in the parent table is called ________.
Respuesta
-
Cascading updates
-
Cascading deletes
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Incremental updates
-
Incremental deletes
Pregunta 8
Pregunta
A surrogate key should be considered when ________.
Respuesta
-
A relationship is N:M
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A composite key is required
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The key contains a lengthy text field
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The key contains a number
Pregunta 9
Pregunta
An attribute that determines which subtype should be used is a(n) ________.
Respuesta
-
Supertype
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Subtype
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Identifier
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Discriminator
Pregunta 10
Pregunta
An entity that holds specialized attributes that distinguish it from one or more other similar entities is a ________.
Respuesta
-
Supertype
-
Parent
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Subtype
-
Discriminator
Pregunta 11
Pregunta
An entity whose existence depends on the presence of another entity but whose identifier does not include the identifier of the other entity is a(n) ________.
Respuesta
-
ID-dependent entity
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Strong entity
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Subtype entity
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Weak entity
Pregunta 12
Pregunta
An entity whose identifier includes the identifier of another entity is a(n) ________.
Respuesta
-
Required Entity
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Weak Entity
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Optional Entity
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Strong Entity
Pregunta 13
Pregunta
An identifier may be ________.
Respuesta
-
Optional
-
A relationship
-
Minimal
-
Composite
Pregunta 14
Pregunta
An occurrence of a particular entity is called an ________.
Respuesta
-
Entity relationship
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Entity class
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Entity attribute
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Entity instance
Pregunta 15
Pregunta
Each attribute of an entity becomes a(n) ________ of a table.
Respuesta
-
Alternate key
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Primary key
-
Column
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Foreign Key
Pregunta 16
Pregunta
Entities of a given type are grouped into an ________.
Respuesta
-
Entity attribute
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Entity instance
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Entity relationship
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Entity class
Pregunta 17
Pregunta
In a minimum cardinality, minimums are generally stated as ________.
Respuesta
-
0 or 1
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M or N
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1 or N
-
One or many
Pregunta 18
Pregunta
In a relational database design, all relationships are expressed by ________.
Respuesta
-
Creating a supertype
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Creating a subtype
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Creating a primary key
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Creating a foreign key
Pregunta 19
Pregunta
In relational database design, IDdependent entities are not used to ________.
Respuesta
-
handle associative relationships
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represent relationships where the child identifier does not include the key of the parent
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represent N:M relationships
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handle archetype/instance relationships
Pregunta 20
Pregunta
Many-to-many relationships are represented by ________.
Respuesta
-
an intersection table which has M:N relationships with the two tables
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two tables with a 1:N relationship
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two tables with an M:N relationship
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an intersection table which has 1:N relationships with the two tables
Pregunta 21
Pregunta
Many-to-many relationships are represented by ________.
Respuesta
-
an intersection table which has M:N relationships with the two tables
-
two tables with a 1:N relationship
-
two tables with an M:N relationship
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an intersection table which has 1:N relationships with the two tables
Pregunta 22
Pregunta
Maximum cardinality refers to ________.
Respuesta
-
the most instances of one entity class that can be involved in a relationship instance with another entity class
-
whether or not an instance of one entity class is required to be related to an instance of another entity class
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the minimum number of entity classes involved in a relationship
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whether or not an entity is a weak entity
Pregunta 23
Pregunta
Minimum cardinality refers to ________.
Respuesta
-
the most instances of one entity class that can be involved in a relationship with one instance of another entity class
-
whether or not an entity is a weak entity
-
the minimum number of entity classes involved in a relationship
-
whether or not an instance of one entity class is required to be related to an instance of another entity class
Pregunta 24
Pregunta
Recursive relationships can have all of the following maximum cardinalities except ________.
Respuesta
-
1:1
-
N:M
-
1:N
-
M:M
Pregunta 25
Pregunta
Supertype/subtype entities are said to have a(n) ________ relationship.
Respuesta
-
HAS-A
-
Redundant
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IS-A
-
Recursive
Pregunta 26
Pregunta
The binary constraint must cover indicates that ________.
Respuesta
-
a table includes values that must occur in a ternary relationship
-
a binary relationship includes a set of value combinations that must all occur in a ternary relationship
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a specific binary relationship must be included in a ternary relationship
-
a table includes values that must occur in a binary relationship
Pregunta 27
Pregunta
The binary constraint must not indicates that ________.
Respuesta
-
a table includes values that must not occur in a ternary relationship
-
a binary relationship includes value combinations that must not occur in a ternary relationship
-
a table includes values that must not occur in a binary relationship
-
a specific binary relationship must not be included in a ternary relationship
Pregunta 28
Pregunta
The characteristics of a thing are described by its ________.
Respuesta
-
Identifiers
-
Attributes
-
Objects
-
Entities
Pregunta 29
Pregunta
The first step in transforming an extended ER model into a relational database design is to ________.
Respuesta
-
create a table for each relationship
-
create a table for each entity
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remove any recursive relationships
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evaluate the entities against the normalization criteria
Pregunta 30
Pregunta
The identifier of the entity becomes the ________ of the corresponding table.
Respuesta
-
Subtype
-
Supertype
-
Primary Key
-
Foreign Key
Pregunta 31
Pregunta
To represent a multivalued attribute in an E-R model, ________.
Respuesta
-
create a new IDdependent entity with a 1:1 relationship
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create a new weak, but not IDdependent entity with a 1:N relationship
-
create a new IDdependent entity with a 1:N relationship
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create a new strong entity with a 1:1 relationship
Pregunta 32
Pregunta
To represent a one-to-many relationship in a relational database design, ________.
Respuesta
-
an intersection table must be created
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the key of the table on the "many" side is placed in the table on the "one" side
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the key of the parent is placed as a foreign key into the child
-
the key of the child is placed as a foreign key into the parent
Pregunta 33
Pregunta
To represent an archetype/instance pattern in an ER model, ________.
Respuesta
-
create a new ID-dependent entity with a 1:1 relationship
-
create a new ID-dependent entity with a 1:N relationship
-
create a new weak, but not ID-dependent entity with a 1:N relationship
-
create a new strong entity with a 1:1 relationship
Pregunta 34
Pregunta
To represent an association pattern in an E-R model, ________.
Respuesta
-
create a new ID-dependent entity with a N:1 relationships to two parent entities
-
create a new weak, but not ID-dependent entity with a 1:1 relationship to one other entity
-
create a new strong entity with a 1:1 relationship to one other entity
-
create a new ID-dependent entity with a 1:1 relationship to one other entity
Pregunta 35
Pregunta
When an entity has a relationship to itself, we have a(n) ________.
Respuesta
-
supertype/subtype relationship
-
archetype/instance relationship
-
recursive relationship
-
Both supertype/subtype relationship and recursive relationship are correct
Pregunta 36
Pregunta
When representing a 1:1 relationship in a relational database design, ________.
Respuesta
-
the intersection table gets the key from both relations
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the key of each table must be placed as foreign keys into the other
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the key of either table may be placed as a foreign key into the other
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the key of both tables must be the same
Pregunta 37
Pregunta
When representing a onetomany relationship in a relational database design, ________.
Respuesta
-
the parent is always on the one side of the "one-to-many" relationship
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either parent or child can be on the one side of the "one-to-many" relationship, and the choice is arbitrary
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either parent or child can be on the one side of the "one-to-many" relationship, and special criteria indicate which table should be on the one side
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the child is always on the one side of the "one-to-many" relationship
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