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A circle across the relationship line near an entity indicates ________.
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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"
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A composite attribute is an attribute that ________.
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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
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A for-use-by pattern must involve what kind of entity?
Frage 4
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A hash mark across the relationship line near an entity indicates ________.
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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"
Frage 5
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A line-item pattern must involve what kind of entity?
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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 ________.
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Incremental updates
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Incremental deletes
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Cascading deletes
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Cascading updates
Frage 7
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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 ________.
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Cascading updates
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Cascading deletes
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Incremental updates
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Incremental deletes
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A surrogate key should be considered when ________.
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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
Frage 9
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An attribute that determines which subtype should be used is a(n) ________.
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Supertype
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Subtype
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Identifier
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Discriminator
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An entity that holds specialized attributes that distinguish it from one or more other similar entities is a ________.
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Supertype
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Parent
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Subtype
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Discriminator
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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) ________.
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ID-dependent entity
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Strong entity
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Subtype entity
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Weak entity
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An entity whose identifier includes the identifier of another entity is a(n) ________.
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Required Entity
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Weak Entity
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Optional Entity
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Strong Entity
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An identifier may be ________.
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Optional
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A relationship
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Minimal
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Composite
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An occurrence of a particular entity is called an ________.
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Entity relationship
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Entity class
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Entity attribute
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Entity instance
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Each attribute of an entity becomes a(n) ________ of a table.
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Alternate key
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Primary key
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Column
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Foreign Key
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Entities of a given type are grouped into an ________.
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Entity attribute
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Entity instance
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Entity relationship
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Entity class
Frage 17
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In a minimum cardinality, minimums are generally stated as ________.
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0 or 1
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M or N
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1 or N
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One or many
Frage 18
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In a relational database design, all relationships are expressed by ________.
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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
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In relational database design, IDdependent entities are not used to ________.
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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
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Many-to-many relationships are represented by ________.
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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
Frage 21
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Many-to-many relationships are represented by ________.
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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
Frage 22
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Maximum cardinality refers to ________.
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the most instances of one entity class that can be involved in a relationship instance with another entity class
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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
Frage 23
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Minimum cardinality refers to ________.
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the most instances of one entity class that can be involved in a relationship with one instance of another entity class
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whether or not an entity is a weak entity
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the minimum number of entity classes involved in a relationship
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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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Recursive relationships can have all of the following maximum cardinalities except ________.
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Supertype/subtype entities are said to have a(n) ________ relationship.
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HAS-A
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Redundant
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IS-A
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Recursive
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The binary constraint must cover indicates that ________.
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a table includes values that must occur in a ternary relationship
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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
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a table includes values that must occur in a binary relationship
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The binary constraint must not indicates that ________.
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a table includes values that must not occur in a ternary relationship
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a binary relationship includes value combinations that must not occur in a ternary relationship
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a table includes values that must not occur in a binary relationship
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a specific binary relationship must not be included in a ternary relationship
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The characteristics of a thing are described by its ________.
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Identifiers
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Attributes
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Objects
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Entities
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The first step in transforming an extended ER model into a relational database design is to ________.
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create a table for each relationship
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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
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The identifier of the entity becomes the ________ of the corresponding table.
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Subtype
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Supertype
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Primary Key
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Foreign Key
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To represent a multivalued attribute in an E-R model, ________.
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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
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create a new IDdependent entity with a 1:N relationship
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create a new strong entity with a 1:1 relationship
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To represent a one-to-many relationship in a relational database design, ________.
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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
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the key of the child is placed as a foreign key into the parent
Frage 33
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To represent an archetype/instance pattern in an ER model, ________.
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create a new ID-dependent entity with a 1:1 relationship
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create a new ID-dependent entity with a 1:N relationship
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create a new weak, but not ID-dependent entity with a 1:N relationship
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create a new strong entity with a 1:1 relationship
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To represent an association pattern in an E-R model, ________.
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create a new ID-dependent entity with a N:1 relationships to two parent entities
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create a new weak, but not ID-dependent entity with a 1:1 relationship to one other entity
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create a new strong entity with a 1:1 relationship to one other entity
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create a new ID-dependent entity with a 1:1 relationship to one other entity
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When an entity has a relationship to itself, we have a(n) ________.
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supertype/subtype relationship
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archetype/instance relationship
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recursive relationship
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Both supertype/subtype relationship and recursive relationship are correct
Frage 36
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When representing a 1:1 relationship in a relational database design, ________.
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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
Frage 37
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When representing a onetomany relationship in a relational database design, ________.
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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