Second exam quizlet

The process of defining one or more subtypes of a supertype and forming relationships is called: specialization. generalization. creating discord. selecting classes.

specialization.

An attribute (or attributes) that uniquely identifies each row in a relation is called a: column. foreign field. primary key. duplicate key

primary key.

Indexes are created in most RDBMSs to: provide a quicker way to store data. decrease the amount of disk space utilized. provide rapid random and sequential access to base-table data. increase the cost of implementation.

provide rapid random and sequential access to base-table data.

A ________ limits the set of permissible values a field may assume. range control null value control primary key candidate key

range control

An integrity control supported by a DBMS is substitute estimates. security. range control. GUI guards.

range control.

A rule that states that each foreign key value must match a primary key value in the other relation is called the: referential integrity constraint. key match rule. entity key group rule. foreign/primary match rule.

referential integrity constraint.

A two-dimensional table of data is called a: group. set. declaration. relation.

relation.

Packaged data models: are ready to use right out of the box. require customization. allow partial specialization. cannot be used for most applicati

require customization.

A single value returned from an SQL query that includes an aggregate function is called a(n) agate. scalar aggregate. vector aggregate. summation.

scalar aggregate

One field or combination of fields for which more than one record may have the same combination of values is called a(n): secondary key. index. composite key. linked key.

secondary key.

A key decision in the physical design process is knowing the user base. selecting structures. deciding on the monitor. All of these.

selecting structures.

A detailed coding scheme recognized by system software for representing organizational data is called a(n): DBMS code. data type. SQL. DB layout.

data type.

The value a field will assume unless the user enters an explicit value for an instance of that field is called a: default value. null value. range control. gurand.

default value.

Designing physical files requires ________ of where and when data are used in various ways. maps descriptions keys hints

descriptions

A nonkey attribute is also called a(n): column. unimportant datum. descriptor. address.

descriptor.

The attribute on the left-hand side of the arrow in a functional dependency is the: candidate key. determinant. foreign key. primary key.

determinant.

The most important challenge of customizing a purchased data model is: getting user buy-in. determining the business rules that will be established through the data model. implementation. user training.

determining the business rules that will be established through the data model.

The ________ rule specifies that an entity can be a member of only one subtype at a time. exclusion disjoint removal inclusion

disjoint

A ________ addresses whether an instance of a supertype may simultaneously be a member of two or more subtypes. disjointedness constraint disjoint rule partial specialization total specialization

disjointedness constraint

Any create command may be reversed by using a ________ command. truncate drop delete unpack

drop

A ________ view is materialized when referenced virtual dynamic materialized base

dynamic

In most cases the goal of ________ dominates the design process. efficient data processing security quick pointer updates shorter design times

efficient data processing

When identifying with the parts of the packaged data model that apply to your organization, you should first start with: entities. attributes. primary keys. relationships.

entities.

The ________ states that no primary key attribute may be null. referential integrity constraint entity integrity rule partial specialization rule range domain rule

entity integrity rule

A contiguous section of disk storage space is called a(n)' track. sector. extent. tablespace

extent.

The smallest unit of application data recognized by system software is a: field. row. data type. column.

field.

A(n) ________ is a technique for physically arranging the records of a file on secondary storage devices. physical pointer retrieval program file organization update program

file organization

When all multivalued attributes have been removed from a relation, it is said to be in: first normal form. second normal form. Boyce-Codd normal form. third normal form.

first normal form.

An attribute in a relation of a database that serves as the primary key of another relation in the same database is called a: link attribute. link key. foreign key. foreign attribute.

foreign key.

A constraint between two attributes is called a(n): functional relation. attribute dependency. functional dependency. functional relation constraint.

functional dependency.

The process of defining a more general entity type from a set of more specialized entity types is called: generalization. specialization. normalization. None of these.

generalization.

A file organization that uses hashing to map a key into a location in an index where there is a pointer to the actual data record matching the hash key is called a: hashed file organization. hash key. multi-indexed file organization. hash index table.

hash index table.

A(n) ________ is a routine that converts a primary key value into a relative record number. record index calculator index pointer program hashing algorithm pointing algorithm

hashing algorithm

An attribute that may have more than one meaning is called a(n): homonym. alias. double defined attribute. synonym.

homonym

A domain definition consists of the following components EXCEPT domain name. data type. integrity constraints. size.

integrity constraints

An index on columns from two or more tables that come from the same domain of values is called a: bitmap index. multivalued index. join index. transaction index.

join index.

The third step in the data modeling process with a packaged data model is: rename identified data elements. rename relationships. map data to be used from package to data in current databases. interview users.

map data to be used from package to data in current databases.

All of the following are the main goals of normalization EXCEPT: minimize data redundancy. simplify the enforcement of referential integrity. maximize storage space. make it easier to maintain data

maximize storage space

All of the following are advantages of packaged data models EXCEPT: packaged data models can be built using proven components evolved from cumulative experiences. projects take less time and cost less. the data model is easier to evolve. more one-to-one relationships give the data model more flexibility.

more one-to-one relationships give the data model more flexibility.

The entity integrity rule states that: no primary key attribute can be null. referential integrity must be maintained across all entities. each entity must have a primary key. a primary key must have only one attribute

no primary key attribute can be null.

An attribute of the supertype that determines the target subtype(s) is called the: determinant. subtype decision. disjoint indicator. None of these.

none of these

In a supertype/subtype hierarchy, each subtype has: only one supertype. many supertypes. at most two supertypes. at least one subtype.

only one supertype.

While Oracle has responsibility for managing data inside a tablespace, the tablespace as a whole is managed by the: user. database administrator. application developer. operating system.

operating system.

The ________ rule states that an entity instance can simultaneously be a member of two (or more) subtypes. disjoint overlap partial specialization total specialization

overlap

The subtype discriminator is a composite attribute when there is a(n): overlap rule. disjoint rule. partial specialization. full specialization.

overlap rule.

A functional dependency in which one or more nonkey attributes are functionally dependent on part, but not all, of the primary key is called a ________ dependency. partial key-based partial functional cross key merged relation

partial functional

The ________ rule specifies that an entity instance of a supertype is allowed not to belong to any subtype. semi-specialization total specialization partial specialization disjointedness

partial specialization

A form of database specification that indicates all the parameters for data storage that are then input to database implementation is: logical. physical. schematic. conceptual.

physical.

A(n) ________ is a field of data used to locate a related field or record. key index lock pointer

pointer

In which data model would a code table appear? Conceptual Logical Physical Data layout

Physical

DDL is typically used during which phases of the development process? Implementation Physical design Analysis All of these

Physical design

Physical database design decisions must be made carefully because of impacts on: data accessibility. response times. security. All of these.

All of these.

A primary key that consists of more than one attribute is called a: foreign key. composite key. multivalued key. cardinal key.

composite key.

An understanding of how to merge relations is important because: there may be a need to merge relations on projects with subteams. different views may need to be integrated. new data requirements may produce new relations to be merged. All of these.

All of these

The relational data model consists of which components? Data structure Data manipulation Data integrity All of these

All of these

Which of the following anomalies result from a transitive dependency? Insertion Modification Deletion All of these

All of these

Which of the following are anomalies that can be caused by redundancies in tables? Insertion Deletion Modification All of these

All of these

Which of the following are properties of relations? Each attribute has a unique name. No two rows in a relation are identical. There are no multivalued attributes in a relation. All of these.

All of these

A factor to consider when choosing a file organization is: fast data retrieval. security. efficient storage. All of these.

All of these.

A method for handling missing data is to: substitute and estimate for the missing data. track missing data with special reports. perform sensitivity testing. All of these.

All of these.

A requirement to begin designing physical files and databases is: normalized relations. definitions of each attribute. technology descriptions. All of these.

All of these.

A rule of thumb for choosing indexes is to: be careful indexing attributes that may be null. index each primary key of each table. use an index when there is variety in attribute values. All of these.

All of these.

________ is a component of the relational data model included to specify business rules to maintain the integrity of data when they are manipulated. Business rule constraint Data integrity Business integrity Data structure

Data integrity

Given the following entities, which of the choices below would be the most complicated? Automobile: VIN, EngineSize, NumberOfDoors, NumberOfPassengers, FuelType, TransmissionSUV: VIN, EngineSize, NumberOfPassengers, NoWheelDrive, FuelType, TransmissionTruck: VIN, EngineSize, NoWheelDrive, FuelType, Transmission, Payload Define one vehicle entity type to hold all entities. Define a separate entity type for each entity. Define a supertype called vehicle and make each of the entities subtypes. Keep only the Truck entity type.

Define one vehicle entity type to hold all entities.

In which type of file is multiple key retrieval not possible? Sequential Hashed Indexed Clustered

Hashed

Which type of file is easiest to update? Sequential Hashed Indexed Clustered

Hashed

Which of the following is an objective of selecting a data type? Represent a small number of possible values Maximize storage space Limit security Improve data integrity

Improve data integrity

________ ensures that a value of a field exists in another database table Null value control Referential integrity Domain integrity Index integrity

Referential integrity

Which of the following is NOT a reason to create an instance of a relational schema with sample data? Sample data can be used to improve user communications. Sample data can be used for prototype generation. Sample data can reverse database implementation errors. Sample data provide a convenient way to check the accuracy of your design

Sample data can reverse database implementation errors.

A relation that contains no multivalued attributes and has nonkey attributes solely dependent on the primary key but contains transitive dependencies is in which normal form? First Second Third Fourth

Second

Which type of file is most efficient with storage space? Sequential Hashed Indexed Clustered

Sequential

Which of the following is a generic entity type that has a relationship with one or more subtypes? Megatype Supertype Subgroup Class

Supertype

The storage format for each attribute from the logical data model is chosen to maximize ________ and minimize storage space. query design programmer productivity data integrity data integration

data integrity

Which of the following is a completeness constraint? Total specialization Partial generalization Total recall Partial hybridization

Total specialization

In an SQL statement, which of the following parts states the conditions for row selection? Select From Where Group By

Where

Given a table named store with 5 fields: store_id, address, city, state, zipcode, why would the following insert command not work? insert into store values ('234 Park Street') It would work just fine. You must specify the fields to insert if you are only inserting some of the fields. There is no table keyword. None of these.

You must specify the fields to insert if you are only inserting some of the fields.

All of the following are common denormalization opportunities EXCEPT: two entities with a one-to-one relationship. a one-to-many relationship. a many-to-many relationship with nonkey attributes. reference data.

a one-to-many relationship.

A good method for identifying inconsistencies and finding hidden meaning in the customized purchased data model is: data analysis. data volume usage analysis. user interviews. data profiling.

data profiling.

An alternative name for an attribute is a(n): synonym. alias. alternate attribute. related characteristic.

alias.

The SQL command ________ adds one or more new columns to a table. create table alter table create view create relationship

alter table

The property by which subtype entities possess the values of all attributes of a supertype is called: hierarchy reception. class management. attribute inheritance. generalization.

attribute inheritance.

All of the following are valid datatypes in Oracle 11g EXCEPT: varchar2. boolean. blob. number.

boolean

Sensitivity testing involves: checking to see if your teeth hurt when you brush. seeing how accurate data are. checking to see if missing data will greatly impact results. None of these.

checking to see if missing data will greatly impact results.

A(n) ________ constraint is a type of constraint that addresses whether an instance of a supertype must also be an instance of at least one subtype. disjoint overlap completeness weak

completeness

In the SQL language, the ________ statement is used to make table definitions. create session create table create index select

create table

When a regular entity type contains a multivalued attribute, one must: create a single relation with multiple lines for each instance of the multivalued attribute. create two new relations, one containing the multivalued attribute. create two new relations, both containing the multivalued attribute. None of these.

create two new relations, one containing the multivalued attribute

The SQL command ________ defines a logical table from one or more tables or views. create table alter table create view create relationship

create view

In a supertype/subtype hierarchy, subtypes that are lower in the hierarchy inherit attributes from not only their immediate supertype but from all ________ in the hierarchy. subtypes supertypes constraints dimensions

supertypes

Two or more attributes having different names but the same meaning are called: homonyms. aliases. synonyms. alternate attributes

synonyms.

Within Oracle, the named set of storage elements in which physical files for database tables may be stored is called a(n): extent. table. tablespace. partition.

tablespace.

A candidate key must satisfy all of the following conditions EXCEPT: the key must uniquely identify the row. the key must indicate the row's position in the table. the key must be nonredundant. each nonkey attribute is functionally dependent upon it.

the key must indicate the row's position in the table.

Subtypes should be used when: there are attributes that apply to some but not all instances of an entity type. supertypes relate to objects outside the business. the instances of a subtype do not participate in a relationship that is unique to that subtype. None of these.

there are attributes that apply to some but not all instances of an entity type.

The ________ rule specifies that each entity instance of the supertype must be a member of some subtype in the relationship. semi-specialization total specialization partial specialization total convergence

total specialization

A functional dependency between two or more nonkey attributes is called a: partial functional dependency. partial nonkey dependency. transitive dependency. partial transitive dependency.

transitive dependency.

A generic or template data model that can be reused as a starting point for a data modeling project is called a(n): packaged data model. universal data model. enterprise data model. None of these.

universal data model.

All of the following are objectives when selecting a data type EXCEPT: represent all possible values. improve data integrity. support all data manipulations. use a lot of storage space.

use a lot of storage space.

All of the following are steps to using a packaged data model EXCEPT: identify the parts of the data model that apply to your data modeling situation. utilize all business rules that come with the packaged data model. rename the identified data elements. map data to be used in packages with existing data in the current databases.

utilize all business rules that come with the packaged data model.

Multiple values returned from an SQL query that includes an aggregate function are called: vector aggregates. scalar aggregates. agates. summations.

vector aggregates

A relation that contains minimal redundancy and allows easy use is considered to be: clean. simple. complex. well-structured.

well-structured

Understanding the steps involved in transforming EER diagrams into relations is important because: you must be able to check the output of a CASE tool. there are rarely legitimate alternatives from which to choose. CASE tools can model any situation. None of these.

you must be able to check the output of a CASE tool.