IS385 Chapter 9

Which of the following properties of a relation states that an entry at the intersection of each row and column is single-valued? A) Entries in cells are simple. B) Entries in columns are from the same set of values. C) Each row is unique. D) The sequence of rows is insignificant.

A) Entries in cells are simple.

Which of the following properties should be satisfied when the identifier of the entity type becomes the primary key of the corresponding relation? A) The value of the key must uniquely identify every row in the relation. B) The key should serve as a foreign key in at least two other relations. C) The key must be a composite of a primary key and a secondary key. D) The key should be an intelligent key.

A) The value of the key must uniquely identify every row in the relation.

For a binary many-to-many relationship existing between entity types A and B: A) a separate relation C is created; the primary key of relation C is a composite key consisting of the primary key for each of the two entities in the relationship B) the primary keys of relation A and relation B are designated as functionally dependent attributes C) secondary keys are used to establish the relationship D) place the primary key of either entity in the relation for the other entity or do this for both entities

A) a separate relation C is created; the primary key of relation C is a composite key consisting of the primary key for each of the two entities in the relationship

If an associative entity exists, then: A) a separate relation C is created; the primary key of relation C is a composite key consisting of the primary key for each of the two entities in the relationship B) the primary keys of relation A and relation B are designated as functionally dependent attributes C) secondary keys are used to establish the relationship D) place the primary key of either entity in the relation for the other entity or do this for both entities

A) a separate relation C is created; the primary key of relation C is a composite key consisting of the primary key for each of the two entities in the relationship

Which of the following combines range and hash partitioning by first segregating data by ranges on the designated attribute and then within each of these partitions it further partitions by hashing on the designated attribute? A) composite partitioning B) combined partitioning C) transitive partitioning D) functional partitioning

A) composite partitioning

To convert a relation to second normal form, you decompose the relation into new relations using the attributes, called: A) determinants B) foreign key C) pointer D) relationship key

A) determinants

If order number serves as the primary key in the ORDER relation and also appears as a nonprimary key attribute in the INVOICE relation, then order number is said to be a: A) foreign key B) candidate key C) pointer D) relationship key

A) foreign key

A single name that is used for two or more different attributes best defines: A) homonym B) synonym C) transitive dependency D) alias

A) homonym

The process of converting complex data structures into simple, stable data structures is referred to as: A) normalization B) simplification C) structuring D) process modeling

A) normalization

The primary deliverable from logical database design is: A) normalized relations B) design specifications C) an updated baseline project plan D) a list of alternative design strategies

A) normalized relations

A field of data that can be used to locate a related field or row of data best describes: A) pointer B) marker C) field locator D) reference locator

A) pointer

An entity whose primary key depends on the primary key of another entity is called a: A) referential entity B) candidate entity C) transitive entity D) weak entity

A) referential entity

The most common style for a logical database model is the: A) relational database model B) hierarchical database model C) network database model D) object-oriented database model

A) relational database model

When each nonprimary key attribute is identified by the whole key, the relation is said to be in at least: A) second normal form B) third normal form C) fourth normal form D) fifth normal form

A) second normal form

For a unary M:N relationship: A) the entity type is modeled as one relation; using as its primary key a composite key, a separate relation is created to represent the M:N relationship B) the entity type and the M:N relationship are modeled as one relation; a composite key is used C) separate relations for the class and for each subclass are created; primary and foreign keys are established for each class D) the primary key of the entity on the one side of the relationship serves as a foreign key in the relation on the many side of the relationship

A) the entity type is modeled as one relation; using as its primary key a composite key, a separate relation is created to represent the M:N relationship

When transforming an E-R diagram into normalized relations, the identifier of the entity type becomes: A) the primary key of the corresponding relation B) the foreign key in the corresponding relation C) a nonkey attribute in the corresponding relation D) a secondary key in the corresponding relation

A) the primary key of the corresponding relation

During logical database design, the work of all systems development team members is coordinated and shared through: A) the project dictionary B) scheduled weekly meetings C) the project leader D) JAD sessions

A) the project dictionary

Merging relations is also referred to as: A) view integration B) view consolidation C) encompassing D) normalizing

A) view integration

Which of the following statements is true regarding normalization? A) Normalization is a top-down process. B) Normalization produces a set of well-structured relations that contain all of the data mentioned in system inputs and outputs. C) Through the use of anomalies, stable structures are produced. D) Normalization is an integrity constraint specifying that the value of an attribute in one relation depends on the value of the same attribute in another relation.

B) Normalization produces a set of well-structured relations that contain all of the data mentioned in system inputs and outputs.

Which of the following is not associated with database design? A) Structure the data in stable structures that are not likely to change over time and that have minimal redundancy. B) The preparation of a final conceptual model and the implementation of the database. C) Develop a logical database design from which we can do physical database design. D) Develop a logical database design that reflects the actual data requirements that exist in the forms and reports of an information system.

B) The preparation of a final conceptual model and the implementation of the database.

If a relationship exists among three or more entities, then: A) recursive relationships must be established through the use of recursive foreign keys B) a separate relation with a primary key that is the composite of the primary keys of each of the participating entities is created C) separate relations are established for each class and for each of the subclasses D) use the primary key of relation A as a foreign key in relations B and C

B) a separate relation with a primary key that is the composite of the primary keys of each of the participating entities is created

A binary one-to-many relationship in an E-R diagram is best represented by: A) the creation of a separate relation; the primary key of this new relation is a composite key consisting of the primary key for each of the two entities in the relationship B) adding the primary key attribute (or attributes) of the entity on the one side of the relationship as a foreign key in the relation that is on the many side of the relationship C) adding the primary key attribute (or attributes) of the entity on the many side of the relationship as a foreign key in the relation that is on the one side of the relationship D) creating a relation with a composite primary key and nonkey attributes

B) adding the primary key attribute (or attributes) of the entity on the one side of the relationship as a foreign key in the relation that is on the many side of the relationship

A many-to-many relationship that associates certain items with their component items is called a: A) binary structure B) bill-of-materials structure C) binary relationship D) ternary relationship

B) bill-of-materials structure

Assume the structure of a relation is EMPLOYEE (Emp_ID, Name, Dept, Salary). The number of attributes for this relation would be: A) three B) four C) five D) six

B) four

A particular relationship between two attributes best defines: A) context B) functional dependency C) normal form D) structure

B) functional dependency

A foreign key in a relation that references the primary key values of that same relation is referred to as a: A) secondary key B) recursive foreign key C) composite key D) complex key

B) recursive foreign key

) "Create a relation with primary key and nonkey attributes" is the relational representation for which E-R structure? A) weak entity B) regular entity C) gerund D) IS-A relationship

B) regular entity

Two different names that refer to the same data item best defines: A) homonym B) synonym C) transitive dependency D) alias

B) synonym

Combining all normalized user views into one consolidated logical database model refers to: A) requirements structuring B) view integration C) normalization D) file integration

B) view integration

Which of the following is not a key step in logical database modeling and design? A) Combine normalized data requirements from all user interfaces into one consolidated logical database model. B) Compare the consolidated logical database design with the translated E-R model and produce, through view integration, one final logical database design for the application. C) Model how data flow through an information system, the relationships among the data flows, and how data come to be stored at specific locations. D) Translate the conceptual E-R data model for the application into normalized data requirements.

C) Model how data flow through an information system, the relationships among the data flows, and how data come to be stored at specific locations.

Using relational notation, an attribute of a relation that is the primary key of another relation is indicated by: A) an underline B) a circle C) a dashed underline D) italics

C) a dashed underline

The process of splitting or combining normalized relations into physical tables based on affinity of use of rows and fields best describes: A) normalization B) simplification C) denormalization D) data structure

C) denormalization

A table used to determine the location of rows in a file that satisfy some condition best describes: A) relation B) structure chart C) index D) domain table

C) index

A special field value, distinct from 0, blank, or any other value, that indicates that the value for the field is missing or otherwise unknown best defines: A) transitive value B) primary key C) null value D) pointer

C) null value

The index file organization: A) provides very fast random retrieval on the primary key B) provides slow random retrieval on the primary key C) provides moderately fast random retrieval on the primary key D) does not provide random retrieval on the primary key

C) provides moderately fast random retrieval on the primary key

Relationships between instances of a single entity type are referred to as: A) binary relationships B) transitive relationships C) recursive relationships D) dependent relationships

C) recursive relationships

A named two-dimensional table of data is a: A) network B) tree structure C) relation D) tuple

C) relation

Each regular entity type in an E-R diagram is transformed into a: A) row in a relation B) column in a relation C) relation D) tuple in a relation

C) relation

A data model that represents data in the form of tables or relations is called a: A) hierarchical database model B) network database model C) relational database model D) hybrid database model

C) relational database model

For any relation R, if, for every valid instance of A, that value of A uniquely determines the value of B: A) then a primary dependency exists in the relation B) then A is said to be functionally dependent on B C) then B is said to be functionally dependent on A D) then A and B are candidate keys for the relation

C) then B is said to be functionally dependent on A

When two 3NF relations are merged to form a single relation: A) weak entities are created B) recursive relationships may result C) transitive dependencies may result D) IS-A relationships are formed

C) transitive dependencies may result

Which of the following is not a true statement regarding a relation? A) Each relation consists of a set of named columns and an arbitrary number of unnamed rows. B) Each column in a relation corresponds to an attribute of that relation. C) An entry at the intersection of each row and column has a single value. D) Each row in a relation corresponds to an attribute of that relation.

D) Each row in a relation corresponds to an attribute of that relation.

During physical design, you consider: A) the definitions of each attribute B) the descriptions of where and when data are entered, retrieved, deleted, and updated C) the expectations for response time and data integrity D) all of the above

D) all of the above

The following are steps to transforming an E-R diagram into normalized relations and then merging all the relations into one final, consolidated set of relations except for: A) represent entities B) represent relationships C) normalize the relations D) denormalize the relations

D) denormalize the relations

For a binary one-to-one relationship between two entities A and B, the relationship is represented by: A) adding the primary key of A as a foreign key of B B) adding the primary key of B as a foreign key of A C) combining the two entities into one relation D) either A or B

D) either A or B

For a unary one-to-one relationship between two entities A and B, the relationship is represented by: A) adding the primary key of A as a foreign key of B B) adding the primary key of B as a foreign key of A C) combining the two entities into one relation D) either A or B

D) either A or B

A named set of rows and columns that specifies the fields in each row of the table best describes: A) relation B) data structure C) entity type D) physical table

D) physical table

The relation state specifying that nonprimary key attributes do not depend on other nonprimary key attributes is: A) first normal form B) second normal form C) Boyce-Codd normal form D) third normal form

D) third normal form

A functional dependency between two (or more) nonprimary key attributes in a relation defines a: A) weak dependency B) partial dependency C) simple dependency D) transitive dependency

D) transitive dependency

A relation that contains a minimum amount of redundancy and allows users to insert, modify, and delete rows without errors or inconsistencies is a(n): A) independent relation B) simple relation C) unnormalized relation D) well-structured relation

D) well-structured relation