ISM 4212 Exam 1

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Relational Database Management System

A DBMS that manages data as a collection of tables in which all relationships are represented by common values in related tables

Simple Primary Keys

A single attribute

Structured Query Language (SQL)

A special-purpose programming language designed for managing data in RDBMS

INSERT Statement

Add a full row to a table OR Add a partial row to a table

CREATE Statement

Add a table to a database

Which of the following is NOT a problem with keeping data?

Automation

Prototyping

Brief attempt at conceptual data modeling Define database during development of initial prototype Repeat implementation and maintenance activities with new prototype versions

Components of the Environment

CASE tools Repository DBMS Database Application User Interface Database Administrations System Developers End Users

Databases Provide:

Central repository of shared data Data stored in a standardized, convenient form

Repository

Centralized storehouse of metadata

UPDATE Statement

Change the value of a field of data

A good business rule is all of the following EXCEPT: Precise Checked Distinct Declarative

Checked

Data Control Language (DCL)

Commands that control a database, including administering privileges and committing data

Data Definition Language (DDL)

Commands that define a database, including creating, altering, and dropping tables and establishing constraints

Data Manipulation Language (DML)

Commands that maintain and query a database

CASE Tools

Computer aided software engineering Automates applications

Relationships

Connections between entities EX: customer places an order Used to retrieve desired information from multiple entities

Referential Integrity

Constraint that states that foreign key values of a table must match primary key values of a related table For referential integrity to hold, any field in a table that is declared a foreign key can contain only values from a parent table's primary key or candidate key

The DIKW triangle includes which of the following?

Data Knowledge Information Wisdom

Types of Structured Query Language

Data Definition Language (DDL) Data Manipulation Language (DML) Data Control Language (DCL)

Data Integrity Problem

Data changes in one file could cause inconsistencies in other files

Information

Data processed to increase knowledge in the user Data in context

Metadata

Data that describes the properties and context of user data Data about data EX: datatype

SELECT Statement

Data you want to be returned from the query OR More specific data you want to be returned from the query

Relational Databases

Database technology involving tables that represent entities and primary/foreign keys that represent relationships Saves data in table formats Uses SQL as standard language What we are working with** Most widely used

DROP Statement

Delete a table from a database

DELETE Statement

Delete all rows from a table OR Delete certain rows from a table

Attributes

Descriptions of the entity EX: for a customer: CustomerID, Address, Phone #

When querying a dimensional database, a user went from summarized data to its underlying details. The function that served this purpose is

Drill down

Why use a database?

Duplicate Data problem Data Integrity problem

The three schema architecture includes

External schema, conceptual schema, and internal schema An approach to building information systems and systems information management that originated in the 1970s

Just having data is a good enough reason to need a database.

False

T/F Computerized support is only used for organizational decisions that are responses to external pressures, not for taking advantage of opportunities

False

T/F Successful BI is a tool for the information systems department, but is not exposed to the larger organization

False

T/F: The data names assigned to entities, attributes and relationships do not really matter.

False

T/f Decision support system (DSS) and management information system (MIS) have precise definitions agreed to by practitioners

False

Data Models

Graphical system capturing nature and relationship of data

How does the use of cloud computing affect the scalability of data warehouse?

Hardware resources are dynamically allocated as use increases.

Foreign Keys

Identifiers that enable one table to refer to another table Primary key from one table becomes the foreign key of the other

Unstructured Data

Images, video, documents

Knowledge

Information put into action What we know Declarative (what we know), Procedural (how to do something), Tacit (difficult to transfer to another person), Explicit (readily articulated, codified, accessed and verbalized)

OLTP (Online Transaction Processing) systems are designed/optimized for

Inputs like inserts, updates, deletes in the database

Data Warehouse

Integrated decision support system derived from various operational databases

Key performance indicators (KPIs) are metrics typically used to measure

Internal results

A database schema can be described by all of the following EXCEPT: It's the structure that contains descriptions of the objects created by the user. It's a special purpose programming language. It's the organization of data. It's stored in the data dictionary.

It's a special purpose programming language.

Database system development methods

Life cycle Prototyping Agile

Within a database, an entity will have which of the following: Many instances Output Consensus Multiple attributes

Many instances Multiple Attributes

Agile Development

Methods based on iterative, incremental development Requirements and solutions evolve through collaboration Encourages rapid and flexible response to change

Composite Primary Keys

More than one attribute

Select all of the examples of bad table names listed below: Student Name 4DJB22 Payroll_Report

Name 4DJB22 Payroll_Report

Category: Boolean

Name: Boolean Description: Stores truth values (true, false) EX: Boolean

Category: Text

Name: Char(n) Description: stores string/text characters; fixed length EX: Char(2) Name: Varchar(n) Description: stores string/text characters; fixed length EX: Varchar(255)

Category: Temporal

Name: Date Description: Stores year, month, and day values EX: Date

Category: Number

Name: Integer Description: stores string/text characters; variable length EX: Integer Name: Decimal (p,s) Description: Stores exact numbers; p= precision, s= scale EX: decimal(5,2) 432.10

Structured Data

Numbers, text, dates

Types of Relationships

One to one One to many One to none

Database

Organized collection of logically related data

End Users

People who use applications / data

Database Applications

Personal Two Tier Three Tier Enterprise Resource Planning Data Warehousing

System Developers

Personnel responsible for implementing databases

Database Administrators

Personnel responsible for managing database

SDLC

Phases: Planning, Analysis, Logical Design, Physical Design, Implementation and Maintenance Time consumer, but comprehensive

Application

Programs- software using the data

A constraint that states that the foreign key values of a table must match the primary key values of a related table is called:

Referential Integrity

Database Development Approaches

SDLC- Systems Development Life Cycle Prototyping Agile Development

Basic Select Statement:

Select ---> Column(s) From ---> Table Where ---> Row

Entities

Singular noun describing a person, place, object, event, or concept EX: Student, customer, order, part Composed of attributes

Why we need a database?

Size of data Ease of updating Accuracy Security Redundancy Importance

DBMS

Software for managing database

Database Management System (DBMS)

Software packages that are used to manipulate a database Used to create, maintain, and provide controlled access to user databases Manages data resources like an operating system manages hardware resources

Steps in Table Creation

Starting from a relation: 1. Identify columns that are unique (candidate keys) 2. Select the primary key 3. Identify data types for attributes 4. Identify columns that can/cannot be null 5. Identify primary key key- foreign key mates 6. Create the table

Data

Stored representations of meaningful objects and events Facts and Figures

Database

Storehouse of data

User Interface

Text/graphical displays to users

Wisdom

The knowledge and experience needed to make sensible decisions

What caused the growth of the demand for instant, on-demand access to dispersed information?

The more pressing need to close the gap between the operational data and strategic objectives

Constraints

The number of instanced of one entity that can or must be associated with each instance of another entity

A database management system is a software system that is used to create, maintain, and provide controlled access to user databases

True

T/F During the early days of analytics, data was often obtained from the domain experts using manual processes to build mathematical or knowledge-based models

True

T/F In the 2000s, the DW-driven DSSs began to be called BI systems

True

T/F Interval data are variables that can be measured on interval scales

True

T/F Managing data warehouses requires special methods, including parallel computing and/or Hadoop/Spark

True

T/F Traditional BI systems use a large volume of static data that has been extracted, cleansed, and loaded into a data warehouse to produce reports and analyses

True

T/F in SQL, the UPDATE statement modifies data in an existing row(s)

True

T/F: A data definition is a type of business rule that provides a description of the data

True

T/F: A database management system is a software system that is used to create, maintain, and provide controlled access to user databases

True

T/F: An attribute corresponds to a field in a table

True

T/F: An attribute is a property or characteristic of an entity

True

T/F: An entity instance is a single example of an entity

True

T/F: In an SQL statement, you use the AND, OR and NOT operators for customizing conditions in the WHERE clause.

True

T/F: Relationship cardinality specifies how many of each entity type is allowed in a relationship

True

T/F: The CREATE TABLE SQL statement defines a new table and its columns.

True

The reason we need a database is to allow the data to grow and still be manageable.

True

Personal Database Application

Typical # of Users: 1 Typical Size of Database: Megabytes

Three-Tier Database Application

Typical # of Users: 100-1,000 Typical Size of Database: Gigabytes

Two-Tier Database Application

Typical # of Users: 5-100 Typical Size of Database: Megabytes-Gigabytes

Enterprise Resource Planning

Typical # of Users: >100 Typical Size of Database: Gigabytes-Terabytes

Data Warehousing

Typical # of Users: >100 Typical Size of Database: Terabytes-Petabytes

Primary Keys

Unique identifiers of the table How we can guarantee that all instances are unique No primary key attribute can be null. All primary key fields must have data.

Duplicate Data Problem

Waste of space housing same information in multiple locations

Why is a performance management system superior to a performance measurement system?

because measurement alone has little use without action

A relational database management system involves:

entities and relationships between those entities

Data warehouses provide direct and indirect benefits to organizations. Which of the following is an indirect benefit of data warehouses?

improved customer service

information put into action; what we know (Declarative, Procedural, Tacit, Explicit)

knowledge

database

organized collection of logically related data. software packages that are used to manipulate a database

wisdom

the knowledge and experience needed to make sensible decisions -values, virtues, vision

Big Data often involves a form of distributed storage and processing using Hadoop and MapReduce. One reason for this is

the processing power needed for the centralized model would overload a single computer.

Benefits of the latest visual analytics tools, such as SAS Visual Analytics, include all of the following EXCEPT

they explore massive amounts of data in hours, not days


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