Quiz 9: Designing Databases

One purpose of database design is to structure the data in stable structures,called normalized tables,that are not likely to change over time and that have minimal ________. A)Data B)Space C)Redundancy D)Columns

Logical and ________ database design is typically performed in parallel with other systems design steps. A)Normal B)Physical C)Conceptual D)Normalized

________ database design is driven not only from the previously developed E-R data model for the application or enterprise but also from form and report layouts. A)Logical B)Physical C)Normalized D)De-normalized

In logical database design,we use a process called ________,which is a way to build a data model that has the properties of simplicity,non-redundancy,and minimal maintenance. A)Data modeling B)Database designing C)De-normalization D)Normalization

In most situations,many physical database design decisions are implicit or eliminated when we choose the ________ technologies to use with the application. A)Data management B)System management C)Software management D)SDLC

There are ________ key steps in logical database modeling and design. A)Two B)Three C)Four D)Five

In logical database modeling and design,we combine normalized data requirements from all user interfaces into one consolidated logical database model; this step is called view ________. A)Summation B)Integration C)Addition D)Combination

In logical database modeling and design,we translate the ________ E-R data model for the application or enterprise,developed without explicit consideration of specific user interfaces,into normalized data requirements. A)Normal B)Physical C)Logical D)Conceptual

A(n)________ is an attribute (or combination of attributes)whose value is unique across all occurrences of a relation. A)Composite key B)Primary key C)Identifier D)Index

During logical database design,you must account for every data element on a system input or output form or report and on the ________. A)E-R diagram B)Conceptual design C)Physical design D)Logical design

In a ________ database model,data is represented as a set of related tables or relations. A)Logical B)Conventional C)Relational D)Physical

A relation is a named,________-dimensional table of data.Each relation (or table)consists of a set of named columns and an arbitrary number of unnamed rows. A)Two B)One C)Three D)Four

Each ________ in a relation corresponds to an attribute of that relation. A)Entity B)Data C)Column D)Row

Each ________ of a relation corresponds to a record that contains data values for an entity. A)Column B)Entity C)Attribute D)Row

Entries in cells are simple and an entry at the intersection of each row and column has a ________ value. A)Duplicate B)Single C)Multi D)Repeating

In a relation,each row is unique and uniqueness is guaranteed because the relation has a non-empty ________ key value. A)Unique B)Composite C)Candidate D)Primary

In a relation,the sequence of columns can be interchanged without changing the meaning or use of the ________. A)Relation B)Attribute C)Row D)Primary key

A well-structured relation is a relation that contains a minimum amount of redundancy and that allows users to insert,modify,and delete the rows without error or inconsistencies and is also known as a ________. A)Column B)Row C)Table D)Key

Logical database design is driven not only from the previously developed E-R data model for the application or enterprise but also from form and report layouts.

During logical database design,you must account for every data element on a system input or output-form or report-and on the flow chart.

A foreign key is an attribute (or combination of attributes)whose value is unique across all occurrences of a relation.

A relation is a named,two-dimensional table of data and each relation (or table)consists of a set of named columns and an arbitrary number of unnamed rows.

In an object oriented database model,data is represented as a set of related tables or relations.

In a relational table,each row is unique and uniqueness is guaranteed because the relation has a non-empty primary key value.

An unstructured relation is a relation that contains a minimum amount of redundancy and that allows users to insert,modify,and delete the rows without error or inconsistencies.

What are the five purposes of data design?

What are the four key steps to logical database modeling and design?

What is a relational database model? How do relations differ from nonrelation tables?

________ is a process for converting complex data structures into simple,stable data structures. A)De-normalization B)Normalization C)Database modeling D)Relation

In ________ normal form,each non-primary key attribute is identified by the whole key (what we call full functional dependency). A)First B)Fourth C)Third D)Second

In ________ normal form,non-primary key attributes do not depend on each other (what we call no transitive dependencies). A)First B)Fourth C)Third D)Second

A functional dependency is a particular relationship between two ________. A)Attributes B)Rows C)Databases D)Tables

The result of normalization is that every ________ key attribute depends upon the whole primary key. A)Candidate B)Unique C)Primary D)Non-primary

A relation is in ________ if every non-primary key attribute is functionally dependent on the whole primary key. A)1NF B)2NF C)3NF D)4NF

A functional dependency between ________ key attributes is also called a transitive dependency. A)Non-primary B)Primary C)Composite D)Unique

De-normalization is a process for converting complex data structures into simple,stable data structures.

A relation is in first normal form if every non-primary key attribute is functionally dependent on the whole primary key.

A relation is in third normal form if it is in second normal form and there are no functional dependencies between two (or more)non-primary key attributes.

Each relationship in an E-R diagram must be represented in the relational database design and how we represent a relationship depends on its nature.

Describe normalization rules.

A ________ is an attribute that appears as a non-primary key attribute in one relation and as a primary key attribute (or part of a primary key)in another relation. A)Referential integrity B)Primary key C)Foreign key D)Unique key

A(n)________ must satisfy referential integrity,which specifies that the value of an attribute in one relation depends on the value of the same attribute in another relation. A)Foreign key B)Primary key C)Unique key D)Index

Each entity type in the E-R diagram becomes a relation.The identifier of the entity type becomes the ________ of the relation,and other attributes of the entity type become non-primary key attributes of the relation. A)Foreign key B)Index C)Unique key D)Primary key

Each regular entity type in an E-R diagram is transformed into a(n)________. A)Identifier B)Relation C)Attribute D)Row

The key should be ________; that is,no attribute in the key can be deleted without destroying its unique identification. A)De-normalized B)Normalized C)Redundant D)Non-redundant

________ is NOT a valid degree of the relationship. A)Binary B)Unary C)N-ary D)Ternary

A binary one-to-many (1:N)relationship in an E-R diagram is represented by adding the primary key attribute (or attributes)of the entity on the one side of the relationship as a(n)________ in the relation that is on the many side of the relationship. A)Primary key B)Foreign key C)Unique key D)Index

A unary relationship is a relationship between the instances of a ________ entity type,which are also called recursive relationships. A)Single B)Double C)Triple D)Many

A recursive foreign key is a foreign key in a relation that references the ________ values of that same relation. A)Non-primary key B)Unique key C)Primary key D)Foreign key

While representing an entity,each non-key attribute of the entity type becomes a key attribute of the relation.

The procedure for representing relationships depends on both the degree of the relationship and not on the cardinalities of the relationship.

A recursive foreign key is a foreign key in a relation that references the foreign key values of that same relation.

Which relation is created with the primary key associated with the relationship or associative entity,plus any non-key attributes of the relationship or associative entity and the primary keys of the related entities (as foreign key attributes)? A)Associative entity B)Associative entity with its own key C)Associative entity with additional key D)Binary 1:N relationship

Which relation is created with a composite primary key using the primary keys of the related entities and additional primary key attributes associated with the relationship or associative entity,plus any non-key attributes of the relationship or associative entity? A)Binary 1:N relationship B)Associative entity C)Associative entity with its own key D)Associative entity with additional key

Which relation is created with a composite primary key using the primary keys of the related entities,plus any non-key attributes associative entity of the relationship or associative entity? A)Associative entity B)Associative entity with its own key C)Associative entity with additional key D)Weak entity

Which relation is created by placing the primary key of the entity on the one side of the relationship as a foreign key in the relation for the entity on the many side? A)Associative entity B)Weak entity C)Binary 1:N relationship D)Associative entity with additional key

Which relation is created by placing the primary key of either entity in the relation for the other entity or by doing this for both entities? A)Binary 1:N relationship B)Unary 1:1 relationship C)Weak entity D)Associative entity with additional key

Which relation is created with a composite primary key (which includes the primary key of the entity on which this weak entity depends)and non-key attributes? A)Associative entity with additional key B)Super-type C)Regular entity D)Weak entity

Which relation is created with primary key and non-key attributes only? A)Regular entity B)Weak entity C)Sub-type D)Associative entity

In some situations,two or more attributes may have different names but the same meaning,as when they describe the same characteristic of an entity.Such attributes are called ________. A)Homonyms B)Antonyms C)Synonyms D)Duplicates

In some situations,a single attribute name,called a(n)________,may have more than one meaning or describe more than one characteristic. A)Homonym B)Antonym C)Synonym D)Duplicate

When merging relations that contain synonyms,we should obtain,if possible,agreement from users on a single standardized name for the attribute and eliminate the other synonym.

When two 3NF relations are merged to form a single relation,dependencies between non-keys may result.

Summarize the four steps involved in transforming an E-R diagram into normalized relations and then merging them into one consolidated set of relations.

Describe how a binary one-to-one relationship is represented.

Describe at least three E-R structures and their relational representation.

Describe the problems that may occur when integrating relations.

A(n)________ is the smallest unit of application data recognized by system software,such as a programming language or database management system. A)Table B)Field C)Row D)Index

Normalized relations are,of course,the result of ________ database design. A)Physical B)Logical C)Conceptual D)Conventional

We begin the physical design phase by addressing the design of physical fields for each attribute in a ________ data model. A)Conventional B)Conceptual C)Physical D)Logical

A(n)________ is a coding scheme recognized by system software for representing organizational data. A)Data model B)Attribute C)Data type D)Field

A default value is the value that a ________ will assume unless an explicit value is entered for it. A)Field B)Row C)Table D)Data type

A ________ value is a special field value,distinct from a zero,blank,or any other value,that indicates that the value for the field is missing or otherwise unknown. A)Key B)True C)Null D)Default

A ________ table is a named set of rows and columns that specifies the fields in each row of the table. A)Conceptual B)Physical C)Relational D)Logical

________ is the process of splitting or combining normalized relations into physical tables based on affinity of use of rows and fields. A)Partitioning B)Modeling C)Normalization D)De-normalization

The capability to split a table into separate sections,often called ________,is possible with most relational database products. A)Partitioning B)Splitting C)Combining D)Normalizing

________ is NOT a valid type of partitioning method in relational database products. A)Range B)Hash C)Boundary D)Composite

Each partition is stored in a separate contiguous section of disk space,which Oracle calls a(n)________. A)Database B)Tablespace C)Table D)Index

A computer operating system stores data in a ________,which is a named set of table rows stored in a contiguous section of secondary memory. A)Disk B)Tablespace C)Table D)Physical file

A(n)________ is a field of data that can be used to locate a related field or row of data. A)Index B)Pointer C)Secondary key D)Attribute

A(n)________ is a file organization in which rows are stored either sequentially or non-sequentially,and an index is created that allows software to locate individual rows. A)Indexed file organization B)Sequential file organization C)Hashed file organization D)Physical file

A(n)________ is one field or a combination of fields for which more than one row may have the same combination of values. A)Index B)Primary key C)Secondary key D)Pointer

In a hashed file organization,the address of each ________ is determined using an algorithm. A)Constraint B)Key C)Column D)Row

The ________ families of file organizations cover most of the file organizations we will have at our disposal as we design physical files and databases. A)Two B)Three C)Four D)Five

A calculated field is a field that can be derived from other database fields and is also known as a computed field or a derived field.

In a range control,only alphabetic data may have a limited set of permissible values.

A null value is a special field value,similar to a zero,blank,or any other value,that indicates that the value for the field is missing or otherwise unknown.

A null value is the value a field will assume unless an explicit value is entered for the field.

A physical table is a named set of rows and columns that specifies the fields in each column of the table.

The capability to split a table into separate sections is possible with most relational database products.

In range partitioning,a table row is assigned to a partition by an algorithm and then maps the specified attribute value to a partition.

Range partitioning 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.

De-normalization can increase the chance of errors and inconsistencies that normalization avoided.

What information is required to design the physical files and databases related to the project?

What is data type? Why is it important to a designer?

List and describe the popular data integrity control methods.You may use examples to explain the control method.

What is null value? Why is it useful in the database?

What is the difference between logical database design and the physical table design?

What is file organization? How does a database designer choose a type of file organization for a specific file?

Describe the three families of file organization.