Introduction to Database

Today’s Lateral Thinking Puzzle “ A woman has incontrovertible proof in court that her husband was murdered by her sister. The judge declares, "This is the strangest case I've ever seen. Though it's a cut-and-dried case, this woman cannot be punished." “ A woman has incontrovertible proof in court that her husband was murdered by her sister. The judge declares, "This is the strangest case I've ever seen. Though it's a cut-and-dried case, this woman cannot be punished."

IT Review Overview

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What is Data?

The “I” in Information Technology and Information Systems Do You Remember?

Data represents a fact or statement of event without relation to other things. Ex: It is raining. Ex: It is raining.Definition “Data is the elementary description of things, events, activities and transactions that are recorded, classified and stored but are not organized to convey any specific meaning.” “Data is the elementary description of things, events, activities and transactions that are recorded, classified and stored but are not organized to convey any specific meaning.” Data vs. Information vs. Knowledge Do You Remember?

Information embodies the understanding of a relationship of some sort, possibly cause and effect. Ex: The temperature dropped 15 degrees and then it started raining. Ex: The temperature dropped 15 degrees and then it started raining.Definition “Information is Data organized so that they have meaning and value to the recipient.” “Information is Data organized so that they have meaning and value to the recipient.” Data vs. Information vs. Knowledge Do You Remember?

Data Hierarchy Bit (a binary digit): a circuit that is either on or off. group of 8 bits, representing a single character, is called a ? A group of 8 bits, representing a single character, is called a ? Do You Remember?

Data Hierarchy (Continued) Field: name, number, or characters that describe an aspect of a business object or activity. Record: collection of related data fields. Table: collection of related records. Database: a collection of integrated and related tables.

What is a Database?

Terminology Database: A collection of tables with relationships between the tables. bibliographic, statistical, business data, images, etc. bibliographic, statistical, business data, images, etc. Database management system (DBMS) is a set of programs that provide users with tools to add, delete, access and analyze data stored in one location.

Tables and Databases Table: A collection of records or documents dealing with one organization, person, area or subject Manual (paper) files Manual (paper) files Computer files Computer files

From Files to Databases Problems with File Systems Inconsistent Data Inconsistent Data Inflexibility Inflexibility Limited Data Sharing Limited Data Sharing Poor enforcement of standards Poor enforcement of standards Excessive program maintenance Excessive program maintenance

Intermission Artwork © Jan’s Courtyard

Database and the Enterprise

DBMS Advantages  Make it easier to store large quantities of information  Make it easier to retrieve information quickly and flexibly  Make it easy to organize and reorganize information  Make it easy to print and distribute information in a variety of ways

DBMS Advantages (cont.) Minimal Data Redundancy Minimal Data Redundancy Consistency of Data Consistency of Data Integration of Data Integration of Data Data Accessibility and Responsiveness Data Accessibility and Responsiveness Data Independence Data Independence Ease of Application Development Ease of Application Development Reduced Program Maintenance Reduced Program Maintenance Sharing of Data Sharing of Data

Database Operations Import: receive data in the form of text files Import: receive data in the form of text files Browse: navigate through information Browse: navigate through information Query: find records that match specific criteria Query: find records that match specific criteria Sort: rearrange records (alphabetically or numerically) Sort: rearrange records (alphabetically or numerically) Print reports, labels, and form letters: A report is an ordered list of selected records and fields in an easy-to-read format. Print reports, labels, and form letters: A report is an ordered list of selected records and fields in an easy-to-read format.

The Many Faces of Databases Large databases often contain hundreds of interrelated tables. Large databases often contain hundreds of interrelated tables. A DBMS can shield users from the complex inner workings of the system, providing them with only the information they need to get their jobs done. A DBMS can shield users from the complex inner workings of the system, providing them with only the information they need to get their jobs done.

Which of the following uses a database for electronic commerce?

Databases in the Real World: Electronic Commerce

Intermission Artwork © Jan’s Courtyard

In Pictures: Technology Billionaires Special Report The Forbes ONE BILLION DOLLARS IS NO LONGER ENOUGH…

Byte Byte Kilobyte (KB) Kilobyte (KB) Megabytes (MB) Megabytes (MB) Gigabytes (GB) Gigabytes (GB) Terabytes (TB) Terabytes (TB) Petabytes (PB) Petabytes (PB) = 8 bits = 1 Thousand Bytes = 1 Million Bytes = 1 Billion Bytes = 1 Trillion Bytes = 1000 Terabytes How Big is BIG? Do You Remember?

How Big is BIG? NSA Call Tracking 96 gigabytes 96 gigabytes AT&T “Daytona” Project 312 terabytes 312 terabytesWal-Mart 583 terabytes 583 terabytes Google Earth Rumored at 1,000 terabytes (1 petabyte) Rumored at 1,000 terabytes (1 petabyte)

Types of Database Systems PC Databases Client/Server Databases Web-Based Databases

PC Databases

Client Server Databases Network Client (Mac/Windows) Database Server (Unix/Linux) Client (Mac/Windows) Client (Mac/Windows)

Databases and the Web  Information is available via a company’s Intranet and the Internet.  HTML, the language used to construct most Web pages, wasn’t designed to build database queries.  XML, a newer, more powerful data description language, is designed with industrial-strength database access in mind.

Databases and the Web Request (ex. get a price quote, place an order) Response (ex. query results with HTML-formatted product price or order confirmation notice)

What Do You Know?

1. A collection of related files, tables, and so on that stores data and the associations among them is _____ A)hardware B)software C)database D)network E)procedures

1. A collection of related files, tables, and so on that stores data and the associations among them is _____ A)hardware B)software C)database D)network E)procedures

2. It is very difficult to manage data for which of the following reasons? A) amount of data increases exponentially over time B) data are scattered throughout organizations C) increasing amount of external data must be considered D) data security is easily compromised E) all of the above

2. It is very difficult to manage data for which of the following reasons? A) amount of data increases exponentially over time B) data are scattered throughout organizations C) increasing amount of external data must be considered D) data security is easily compromised E) all of the above

3. Place the following members of the data hierarchy in the correct order: A)bit – byte – field – record – database – table B)bit – field – byte – record – table – database C)byte – bit – record – field – database D)bit – byte – field – record – table – database

3. Place the following members of the data hierarchy in the correct order: A)bit – byte – field – record – database – table B)bit – field – byte – record – table – database C)byte – bit – record – field – database D)bit – byte – field – record – table – database

4. Data are scattered throughout organizations. A) True B) False

4. Data are scattered throughout organizations. A) True B) False

5. The amount of data is increasing exponentially over time. A) True B) False

5. The amount of data is increasing exponentially over time. A) True B) False

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