Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Data Foundations > Database Basics > Flashcards

Database Basics Flashcards

1
Q

Numeric, textual, visual, or audio information that describes real world systems

A

Data

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is collected and processed to aid in a variety of tasks such as forecasting weather, analyzing financial investments and tracking the global spread of pandemics?

A

Data

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name three ways data can vary.

A

1) Scope
2) Format
3) Access

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the term for the amount of data produced and collected?

A

Scope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the term for the concept that data may be produced as numbers, text, images, audio, or video?

A

Format

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the term for the concept that some data sources are private while others are made publicly available?

A

Access

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Historically, data was blank.

A

Analog

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Historically where were data images stored?

A

Celluloid tapes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Today, data is mostly blank, encoded as zeros and ones on electronic and magnetic media.

A

Digital

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The shift from analog to digital in data facilitated the rise of what?

A

Large computer databases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What website provides thousands of US government data sets?

A

data.gov

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What website allows users to find and publish data sets?

A

kaggle.com

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What website provides data sets in aerospace and other related sciences?

A

data.nasa.gov

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Data relationships are often represented in a graphical format called what?

A

Visualization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What website collects and reports data info relative to cancer?

A

cancer.gov/research

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What website collects data by the New York City government to support continuous monitoring and improvements to NYC and residents’ health.

A

opendata.cityofnewyork.us

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a collection of data in a structured format that can be stored on paper and even clay tablets?

A

database

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Modern what are stored on computers?

A

databases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What ensures that similar data is stored in a standardized manner?

A

Structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Many modern databases contain how many bytes of data and support thousands of simultaneous users?

A

trillions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

A blank, or a blank, is software that reads and writes data in a database, ensures data is secure, internally consistent, and available at all times?

A

Database system, or database management system (DBMS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is a request to retrieve or change data in a database?

A

Query

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is a specialized programming language, designed specifically for database systems?

A

Query language

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is a software that helps business users interact with database systems since databases are complex. and many users don’t know query languages?

A

A database application

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is organized into layers meaning an application interacts with a query language on one layer while the query language interacts with a database system on another layer?

A

Database software

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the term for a software application that manages corporate data for a specific business functions. It usually includes a database system as well as a user interface, business logic, and interacts with other systems?

A

Information management system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the term for the person responsible for securing the database system against unauthorized users, enforces procedures for user access and database availability?

A

Database administrator

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Who determines the format of each element and the overall database structure?

A

Database designer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Who develops computer programs that utilize a database, writing applications that combine database query language and general-purpose programming languages?

A

Database programmer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Who is a consumer of data in a database? They request, update, or use stored data to generate reports or information.

A

Database user

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What requirement helps when many users and apps simultaneously access large databases, query response time degrades rapidly.

A

Performance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Database systems maintain what by structuring data properly on storage media and processing queries efficiently?

A

Fast response times

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What states that many database users should have limited access to specific tables, columns or rows of a database?

A

Authorization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Database systems blank individual users to access specific data.

A

Authorize

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What aspect of database systems ensure authorized users only access permissible data?

A

Security

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Database systems also protect against who by encrypting data and restricting access?

A

Hackers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Database systems ensure data is consistent with blank and blank rules.

A

Structural and business

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Computers, Database systems, and individual transactions occasionally blank.

A

fail

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Database systems must blank from failures and restore the database to a consistent state without loss of data.

A

Recover

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What interprets queries, creates a plan to modify the database or retrieve data, and returns the query results to the application

A

Query processor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is a particularly challenging requirement for database systems?

A

Transaction management

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

A what is a group of queries that must either be completed or rejected as a whole?

A

Transaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Execution of some, but not all, queries results in what?

A

Inconsistent or incomplete data

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

When processing transactions database systems must do what three things?

A

1) process transactions completely or not at all
2) prevent conflicts between concurrent transactions
3) ensure transaction results are never lost

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

The blank of a database system describes the internal components and the relationship between components?

A

Architecture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Name the five common components of a database system

A

Query processor
Storage manager
Transaction manager
Log
Catalog

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What performs query optimization to ensure the most efficient instructions are executed to the data?

A

Query processor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What translates the query processor instructions into low-level file system commands that modify or retrieve data?

A

Storage manager

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Database sizes range from what to what do the storage manager used indexes to quickly locate data?

A

Megabytes terabytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What ensures transactions are properly executed?

A

Transaction manager

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What prevents conflicts between concurrent transactions?

A

Transaction manager

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What restores the database to a consistent state in the event of a transaction system failure?

A

Transaction manager

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What is a file containing a complete record of all insert, updates, and deletes processed by the database?

A

Log

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What writes log records before applying changes to the database?

A

Transaction manager

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

In the event of a failure, the transaction manager uses what to restore the database?

A

Log records

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

The what also known as what is a directory of tables, columns, indexes, and other database objects

A

Catalog
Data dictionary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Other database components use what to process and then execute queries?

A

Catalog information

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What is the term for data about databases, such as column names and the numbers of rows in each table?

A

Metadata

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Database systems store metadata where and use metadata to do what?

A

Catalog
Process queries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Most leading database systems are blank.

A

Relational

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

A blank stores data in tables, columns and rows, similar to a spreadsheet.

A

Relational database

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

All data in a what has the same format?

A

Column

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

All data in a what represents a single object.

A

Row

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

All relational database systems support what?

A

SQL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

What does SQL stand for?

A

Structured query language

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What includes statements that read and write data, create and delete tables, and administer the database system?

A

SQL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

Blank databases are ideal for databases that require an accurate record of every transaction.

A

Relational

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

What is the term for massive volumes of data?

A

Big data

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

The newer non-relational systems are called blank meaning blank and are optimized for big data.

A

NoSQL
Not only SQL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Blank software is software that anyone can inspect, copy, and modify with no licensing fee

A

Open source

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

A blank is a command for a database that typically inserts new data, retrieves data, updates data or deletes data from a database.

A

Query

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

A what is a computer programming language for writing database queries.

A

Query language

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

What does CRUD stand for

A

Create, Read, Update, Delete

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

What inserts new data into the database?

A

Insert query

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

What retrieves information from the database?

A

A select query

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

What changes existing data in the database?

A

An update query

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

What removes data from the database?

A

Delete query

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

Who sponsors the SQL standard?

A

American National Standards Institute (ANSI) and the International organization for standardization (ISO)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

Who developed SQL in the 1970s?

A

IBM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

All relational databases support what?

A

SQL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

What SQL statement creates a new table by specifying the table and column names?

A

CREATE TABLE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

In a create table query, each column is assigned a what?

A

Data type

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

What stores integer values?

A

INT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

What stores fractional number values?

A

DECIMAL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

What stores textual values?

A

VARCHAR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

What stores year, months, and day?

A

DATE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

Some data types are followed by one of two numbers in parentheses indicating the what of the data type?

A

Size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

A what is a specification of database objects such as tables, columns, data types, and indexes?

A

Database design

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

What refers to the process used to develop the specification?

A

Database design

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

For large, complex databases, database design has what three phases?

A

1) Analysis
2) Logical Design
3) physical design

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

The blank phase specifies database requirements without regard to a specific database system.

A

Analysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

Blank are represented as entities, relationships, and attributes.

A

Requirements

93
Q

A blank is a person place activity or thing?

A

Entity

94
Q

A blank is a link between entities.

A

Relationship

95
Q

A blank is a descriptive property of an entity

A

Attribute

96
Q

Blank has many alternative names like conceptual design, entity-relationship modeling, and requirements definition

A

Analysis

97
Q

Entities, relationships, and attributes are depicted in what?

A

ER diagrams

98
Q

In an ER diagram, blank represent entities

A

Rectangles

99
Q

In an ER diagram, blank represent relationships

A

Line between rectangles

100
Q

In an ER diagram, text inside rectangles and below entity names represent what?

A

Attributes

101
Q

The blank phase implements database requirements in a specific database system

A

Logical desigb

102
Q

For relational database systems, logical design converts entities, relationships and attributes into what, what, and what?

A

Tables, keys, and columns

103
Q

A blank is a column used to identify rows of a table

A

Key

104
Q

The logical design is depicted in what that is similar to ER diagrams, but more detailed

A

Table diagram

105
Q

In a table diagram, what represents tables?

A

Rectangles

106
Q

In a table diagram, what appears at the top of rectangles

A

Table name

107
Q

In a table diagram, text within rectangles and below table names represent what?

A

Columns

108
Q

In a table diagram, what indicates key columns

A

A solid bullet

109
Q

In a table diagram, blank indicate columns that refer to keys?

A

Empty bullets

110
Q

The logical design, as specified in SQL, and depicted in a table diagram, is called a what?

A

Database schema

111
Q

The what phase adds indexes and specifies how tables are organized on storage media?

A

Physical design

112
Q

Physical design is specified with sql statements such as blank and, like logical design, is specific to a database system

A

CREATE INDEX

113
Q

In relational databases, logical design affects the query blank while physical design affects the query blank?

A

Results
Processing speed

114
Q

What is the principle that physical design never affects query results called?

A

Data independence

115
Q

Blank allows database designers to tune query performance without changes to application programs?

A

Data independence

116
Q

When database designers modify indexes or row orders, applications run faster or slower but always blank.

A

Generate the same results

117
Q

Blank is a major advantage of relational databases and contributed to rapid adoption of relational tech in the 1980s

A

Data independence

118
Q

Blank is the implementation of requirements as tables, keys, and columns in a specific database system

A

Logical design

119
Q

Blank is the overall process of determining and implementing database requirements

A

Database design

120
Q

Blank is the specification of database requirements without regard to implementation

A

Analysis

121
Q

Blank affects query performance but not query results

A

Physical design

122
Q

What term is synonymous with data independence

A

Information independence

123
Q

Because of what, relational database applications can be programmed before physical design is in place

A

Data independence

124
Q

SQL is the standard relational query language but lacks important blank

A

Programming features

125
Q

To write a database program, sql is usually combined with a what?

A

General purpose programming language

126
Q

To simplify the use of sql with a general purpose language, database programs typically use a what?

A

Application programming interface (API)

127
Q

A blank is a library of procedures or classes that links a host programming language to a database.

A

Application programming interface (API)

128
Q

In an API, the host language calls what, which handle details such as connecting to the database, executing queries, and returning results?

A

Library procedures

129
Q

Blank help bridge the gap between sql and host languages

A

Cursors

130
Q

Blank is a leading relational database system sponsored by Oracle

A

MySQL

131
Q

MySQL runs on all major blank.

A

Operating systems

132
Q

Name the two MySQL editions

A

1) MySQL community, commonly called MySQL Server
2) MySQL Enterprise

133
Q

Which MySQL edition is free for non-commercial apps?

A

MySQL community or MySQL server

134
Q

The MySQL blank is a text interface included in the MySQL server download that allows developers to connect to the database server, perform administrative functions, and execute SQL statements

A

Command-Line Client

135
Q

Some developers prefer to interact with MySQL server via a blank.

A

Graphical user interface

136
Q

Blank is installed in MySQL server and allows developers to execute sql commands using an editor.

A

MySQL workbench

137
Q

MySQL workbench shows the navigator sidebar with two tabs. Name them.

A

Administration
Schemas

138
Q

The blank tab of the MySQL workbench shows various administrative options, like checking the server’s status, importing:exporting data and starting /stopping g the MySQL server

A

Administration

139
Q

The blank tab of the MySQL workbench shows a list of available databases. A database can be expanded to show the database’s tables

A

Schema

140
Q

In the MySQL workbench, the blank panel is where users enter sql statements..

A

Query panel

141
Q

In MySQL workbench, pressing the blank executes the sql statements and shows the results below the query panel.

A

Lightning bolt icon

142
Q

The glossary also contains complete blanks of entities, relationships, and attributes.

A

descriptions

143
Q

The description states the meaning of each entity, relationship, or attribute in blank

A

complete sentences

144
Q

The description begins with the name and includes blank and blank to illustrate usage.

A

examples and counterexamples

145
Q

Name the four steps of discovery

A

1A Identify entities, relationships, and attributes in interviews.
1B Draw ER diagram.
1C List standard attribute types in glossary.
1D Document names, synonyms, and descriptions in glossary.

146
Q

In entity-relationship modeling, blank refers to maxima and minima of relationships and attributes.

A

cardinality

147
Q

Blank is the greatest number of instances of one entity that can relate to a single instance of another entity.

A

Relationship maximum

148
Q

A relationship has two maxima, one for each of the blank.

A

related entities

149
Q

Maxima are usually specified as blank or blank.

A

one or many

150
Q

A related entity is blank when the maximum is one and blank when the maximum is many.

A

singular
plural

151
Q

On ER diagrams, maxima are shown as blank or blank.

A

1 or M

152
Q

Occasionally, relationship maximum is a blank. Ex: Each employee has at most three telephone numbers in the database, and each telephone number belongs to at most one person. The Employee-Has-Telephone maxima are one-three

A

number greater than one

153
Q

Blank is the least number of instances of one entity that can relate to a single instance of another entity.

A

Relationship minimum

154
Q

A relationship has blank, one for each of the related entities.

A

two minima

155
Q

Minima are usually specified as blank or blank

A

zero or one

156
Q

A related entity is blank when the minimum is zero and blank when the minimum is one.

A

optional
required

157
Q

On ER diagrams, minima are shown after maxima in blank.

A

parentheses Ex: M(1) or M(0).

158
Q

Occasionally, relationship minimum is a number blank. Ex: Two forms of identification are required for customers, and each identification document belongs to only one customer. The Customer-Has-Identification minima are one-two.

A

greater than one

159
Q

Blank is the greatest number of attribute values that can describe each entity instance.

A

Attribute maximum

160
Q

Attribute maximum is usually specified as blank or blank.

A

one (singular) or many (plural).

161
Q

Blank is the least number of attribute values that can describe each entity instance.

A

Attribute minimum

162
Q

Attribute minimum is usually specified as blank or blank.

A

zero (optional) or one (required).

163
Q

In ER diagrams, attribute maximum and minimum follow blank.

A

attribute name

164
Q

In ER diagrams, attribute blank appears in parentheses.

A

minimum

165
Q

Occasionally, attribute maximum and minimum are specified as a number rather than blank. Ex: If each person submits exactly two forms of identification, the IDNumber attribute of Person has a maximum and minimum of two.

A

zero, one, or many

166
Q

Each value of a blank describes at most one entity instance.

A

unique attribute

167
Q

A unique attribute is not the same as a blank

A

singular attribute

168
Q

A unique attribute has at most blank for each attribute value

A

one entity instance

169
Q

A singular attribute has at most one blank for each entity instance

A

attribute value

170
Q

In ER diagrams, blank indicates a unique attribute and blank indicates a non-unique attribute. .

A

1
M

171
Q

In ER diagrams, the unique attribute 1 or non-unique M appears before the blank

A

attribute maximum and minimum.

172
Q

In some cases, individual attributes are not unique, but a blank is unique. Ex: Different airlines use the same flight number for different flights. AirlineCode and FlightNumber are not unique attributes of Flight, but the composite (AirlineCode, FlightNumber) is unique.

A

Composite of several attributes

173
Q

Entities have an implicit relationship with their attributes, called blank. Attribute maximum and minimum are the cardinality of the attribute in Entity-Has-Attribute. Ex: Each vehicle has exactly one vehicle identification number, or VIN. So VehicleNumber is singular and required in Vehicle-Has-VehicleNumber.

A

Entity-Has-Attribute

174
Q

An attribute is unique when the blank in Entity-Has-Attribute is singular. Ex: Each VIN describes at most one vehicle. So VehicleNumber is unique and Vehicle is singular in Vehicle-Has-VehicleNumber.

A

entity

175
Q

Name the four steps to determine cardinality

A

2A Determine relationship maxima and minima.
2B Determine attribute maxima and minima.
2C Identify unique attributes.
2D Document cardinality in glossary and, optionally, on ER diagram

176
Q

An blank is unique, singular, and required.

A

identifying attribute

177
Q

Identifying attribute values correspond one-to-one to, or identify, blank.

A

entity instances

178
Q

A blank has one or more identifying attributes

A

strong entity

179
Q

When a strong entity is implemented as a table, one of the identifying attributes may become the blank.

A

primary key.

180
Q

A blank does not have an identifying attribute.

A

weak entity

181
Q

A weak entity usually has a relationship, called an blank, to another entity, called an blank

A

identifying relationship
identifying entity.

182
Q

A weak entity’s blank of the identifying entity is 1(1).

A

cardinality

183
Q

In an ER diagram, an identifying relationship has a blank next to the identifying entity.

A

diamond

184
Q

Cardinality of the identifying entity is always blank, so the diamond replaces the cardinality symbol.

A

1(1)

185
Q

For weak entities, identifying relationships replace blank. Ex: In the animation above, If each project has at most one task, ProjectNumber identifies Task. If each project has many tasks, (ProjectNumber, TaskName) identifies Task. The second attribute, TaskName, must be blank, blank and blank within each project.

A

identifying attributes
singular, required, and unique

186
Q

A weak entity is usually identified by a blank

A

strong identity

187
Q

A weak entity can be identified by another blank or by several blank

A

weak entity
entities.

188
Q

When a weak entity is identified by a weak entity or multiple entities, the blank may be complex.

A

identifying attribute

189
Q

If each task has many subtasks, a blank such as (ProjectNumber, TaskName, SubtaskCode) identifies Subtask.

A

composite attribute

190
Q

The identifying attribute of a weak entity may depend on blank and may not be apparent in the ER diagram.

A

business rules

191
Q

Name the three steps of distinguishing strong and weak entitites

A

3A Identify strong and weak entities.
3B Determine the identifying relationship(s) for each weak entity.
3C Document weak entities and identifying relationships
in glossary and ER diagram.

192
Q

An blank is a set of entity instances

A

entity type

193
Q

A blank entity is a subset of another entity type, called the blank entity. Ex: Managers are a subset of employees, so Manager is a blank entity of the Employee blank entity.

A

subtype
supertype

194
Q

On ER diagrams, subtype entities are drawn within the blank.

A

supertype

195
Q

A supertype entity usually has several blank.

A

subtypes

196
Q

Blank of the supertype apply to all subtypes.

A

Attributes

197
Q

Attributes of a subtype do not apply to blank or the blank.

A

other subtypes or the supertype.

198
Q

A supertype entity identifies its subtype entities. The identifying relationship is called an blank.

A

IsA relationship.

199
Q

Since a supertype entity always identifies its subtypes, the IsA relationship is assumed and can be blank from the ER diagram.

A

omitted

200
Q

Supertype and subtype entities are often created from blank and blank.

A

similar entities and optional attributes.

201
Q

Blank are entities that have many common attributes and relationships.

A

Similar entities

202
Q

Similar entities become blank of a new blank entity

A

subtypes
supertype

203
Q

Common attributes and relationships move to the new blank. Attributes and relationships that are not shared remain with the blank.

A

supertype entity
Subtype entities.

204
Q

An entity with many blank also suggests new supertype and subtype entities.

A

optional attributes

205
Q

The entity with many optional attributes becomes a supertype entity and retains all blank. Optional attributes become required attributes of new blank.

A

Required attributes
subtype entities.

206
Q

Creating a new blank for similar entities, or a new blank for optional attributes, is neither an automatic nor objective decision. Similar entities with many common attributes are good candidates for a blank Entities with many optional attributes are good candidates for a blank.

A

supertype
subtype
new supertype.
new subtype.

207
Q

A blank of a supertype entity is a group of mutually exclusive subtype entities.

A

partition

208
Q

A blank can have several partitions

A

supertype entity

209
Q

Blank within each partition are disjoint and do not share instances.

A

Subtype entities

210
Q

Subtype entities in different partitions blank and do share instances.

A

overlap

211
Q

In diagrams, subtype entities within each partition are blank aligned. Subtype entities in different partitions are blank aligned.

A

vertically
horizontally

212
Q

Each partition corresponds to an optional blank of the supertype entity.

A

partition attribute

213
Q

The partition attribute indicates which blank is associated with each supertype instance.

A

subtype entity

214
Q

Name the four steps of creating supertype and subtype entities

A

4A Identify supertype and subtype entities.
4B Replace similar entities and optional attributes with supertype and subtype entities.
4C Identify partitions and partition attributes.
4D Document supertypes, subtypes, and partitions in glossary and ER diagram.

215
Q

Blank diagram conventions vary widely.

A

ER

216
Q

Blank depicts cardinality as a circle (zero), a short line (one), or three short lines (many).

A

crow’s foot notation

217
Q

Some ER diagrams may depict relationship names inside a blank

A

diamond

218
Q

Some ER diagrams may depict weak entities and identifying relationships with blank

A

double lines

219
Q

Some ER diagrams may depict subtype entities with blank rather than inside of supertype entities.

A

IsARelationships

220
Q

Some ER diagrams may use color, dashed lines, or double lines to convey blank

A

additional information

221
Q

ER modeling concepts also vary. Ex: Some ER models may allow blank between three or more entities.

A

relationships

222
Q

ER modeling concepts also vary. Ex: Some ER models may decompose a complex model into a group of related entities, called a blank.

A

subject area

223
Q

ER modeling concepts also vary. Ex: Some ER models may refer to strong entities as blank and weak entities as blank.

A

independent
dependent

224
Q

Several model conventions are standardized and widely used. Leading conventions include blank is commonly used for software development. Software data structures are similar to database structures, so blank includes ER conventions.

A

Unified Modeling Language, or UML,

225
Q

Several model conventions are standardized and widely used. Leading conventions include blank stands for Information DEFinition version 1X. blank became popular, in part, due to early adoption by the United States Department of Defense.

A

IDEF1X

226
Q

Several model conventions are standardized and widely used. Leading conventions include blank appeared in an early ER modeling paper by Peter Chen. blank is not standardized but often appears in literature and tools.

A

Chen notation

227
Q

An blank is documented in the data model, but not tracked with data in the database. In an ER diagram, blank are distinguished with special notation, such as a dashed rectangle or distinct color.

A

intangible entity

228
Q
A

Data Foundations (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions