# Introduction to Computers/Databases

Course Navigation
| << Previous - Development | Next - AI >> |
Introduction to Computers → Databases
This page is part of the Introduction to Computers project. :

## Basic Structure
### Field

A field is a unit of data which consists of one or more characters or bytes. Examples of a field are name, street address & SIN.
This is important because a collection of fields makes up a record!!

### Key Field

Also known as a 'key', 'keyword' or 'sort key', it is a field which is used to sort data. A field in a record that holds an unique data Mostly it has been used for employee numbers, student numbers, social insurance numbers, customer account numbers, or a combination of letters and numbers that are a meaningful code. It's chosen to exclusively identify a record so that it can be retrieved and processed with ease.
The primary characteristic of the key field is that it is unique. w:Key_field

### Record

A record is a collection of related fields. Each record stores data about only one entry, one entity, which can be a person (name), place (address), a thing (SIN or telephone number), an occurrence (shopping preference, or a phenomenon.
This is important because related records make up a file!.

### Table

A table is a file of related records, and it is located at the top of data hierarchy.

## DBMS

A database management system (DBMS) is computer software designed for the purpose of managing databases. A DBMS is a complex set of software programs that controls the organization, storage, management, and retrieval of data in a database.w:Database_management_system
Benefits of DBMS
1)Improved strategic use of corporate data
2)Reduced complexity of the organization’s information systems environment
3)Reduced data redundancy and inconsistency
4)Enhanced data integrity
5)Application-data independence
6)Improved security
7)Reduced application development and maintenance costs
8)Improved flexibility of information systems
9)Increased access and availability of data and information
w:Database_management_system

### Data Dictionary

Data dictionaries are also a repository. They define the type of data that go into each field. However they do not contain actual data from the database. It's a collection of descriptions of the data objects or items.

### Utilities

These are also known as DBMS utilities; programs which allows you to manage the database, through "creating, editing, and deleting data, records, and files" This enables you to sort your data base by key fields making it easier to find relevant data.

### Report Generator

A program that is used to create reports that will be created by using a database and then producing a printed product or an on-screen product
The format can be specified in advance. Non-exports can create attractive reports on short notice

## Models
### Hierarchical

Database is where fields or records are organized in related groups. The parent records are at the top of the database and children are at the bottom. The structure of a hierarchal database can be visualized as a tree as all data-sets belong under a single heading.
One popular example of the hierarchical model for databases is the LDAP (Lightweight Directory Access Protocol.) Hierarchical Databases are extremely common due to their simplicity and efficiency. This efficiency stems from the fact that the hierarchical model uses 12 parameters as opposed to the bifactorial model which uses 16.

### Network

Database similar to hierarchal database, but each child record can have more than one parent record. Therefore, a child record (AKA: a member) may reach through more than one parent!

### Relational

A relational database is a database structure that relates or connects data in different files through the use of a key field, or common data element. In this arrangement there are no access paths down a hierarchy instead data elements are stored in different tables made up of rows and columns.The relational database is a common database structure and it is more flexible than the hierarchial/ network database

### Object-Oriented

Databases that uses "objects," software written in small, reusable chunks, as elements within database files. An object consists of (1) data in any form and (2) instructions for the action to be taken on the data.
This is important because it can contain photo's, sound bites and video clips!! Woo Hoo!

### Multidimensional

Multidimensional database technology has a multitude of data sources which it uses to analyze large amounts of data for the use of logistics and decision making. It is used primarily in sales and marketing, where specific data is chosen from a database and displayed on a cube. Only three values can be displayed on the cube at one time.

## Data Mining

Data mining is the activity of sifting through large amounts of data and sorting it into useful collections of data. This type of activity is usualy discipline related. w:Data_mining It's name comes from the similarities between looking for valuable business information and mining a mountain for valuable ore.

### Sources

This is the first step in the data mining process. Data comes from many sources... flat files, databases, and others such as online sources. Sources include materials from another company or data base. (tx 411) ie) telemarketing companies

### Fusion

Fusion is the second step in the process of data mining. This is where data is purchased from different sources (internal and external) and fused together.

### Cleaning

Data cleaning is the next step after fusion the data that comes from different sources may be of poor quality and full of errors and inconsistencies, or irrelevant. The source data has to be cleaned to ensure that its free of errors

### Data

This is the relevant information that is acquired such as name, e-mail address or specific purchases that can be input into a database of related information.
Companies will buy the data from the source the collects it, which allows them to create marketing targets.

### Meta-Data

meta- data is extra data that relates to the data acquired for the databases such as country of residence or most frequently shopped store.It is data describing data. For example, a listing that describes what attributes are allowed to be in data sets is called "meta-information".w:Database_management_system
w:Metadata
Metadata is important for two reasons, it allows us to search for items related the the meta-data as well as to provide more information about a subject. w:Meta_data

### Warehouse

A data warehouse is the main repository of an organization's historical data, its corporate memory. Data mining, the extraction of hidden predictive information from large databases, is a powerful new technology with great potential to help companies focus on the most important information in their data warehouses. Data mining tools predict future trends and behaviors, allowing businesses to make proactive, knowledge-driven decisions. The automated, prospective analyses offered by data mining move beyond the analyses of past events provided by retrospective tools typical of decision support systems. Data mining tools can answer business questions that traditionally were too time consuming to resolve. They scour databases for hidden patterns, finding predictive information that experts may miss because it lies outside their expectations. It contains the raw material for management's decision support system. The critical factor leading to the use of a data warehouse is that a data analyst can perform complex queries and analysis, such as data mining, on the information without slowing down the operational systems.
The most commonly used techniques in data mining are:
Artificial neural networks: Non-linear predictive models that learn through training and resemble biological neural networks in structure.
Decision trees: Tree-shaped structures that represent sets of decisions. These decisions generate rules for the classification of a dataset.
Genetic algorithms: Optimization techniques that use processes such as genetic combination, mutation, and natural selection in a design based on the concepts of evolution.
Nearest neighbor method: A technique that classifies each record in a dataset based on a combination of the classes of the k record(s) most similar to it in a historical dataset (where k ³ 1). Sometimes called the k-nearest neighbor technique.
Rule induction: The extraction of useful if-then rules from data based on statistical significance.

## eCommerce

Electronic commerce, commonly known as e-commerce or eCommerce, consists of the buying and selling of products or services over electronic systems such as the Internet and other computer networks. w:Electronic_commerce
E-Commerce became possible with the development of the Electronic Data Interchange (EDI) and the Electronic Funds Transfer (EFT). They were used in the 1970's. w:Ecommerce

### B2B

Business-to-business, or “B2B”, is a term commonly used to describe electronic commerce transactions between businesses. It is a term that originated and is almost exclusively used in electronic commerce and usually takes the form of automated processes between trading partners.
B2B Transactions are more common than B2C transactions due to the reluctance of consumers to adopt electronic commerce technologies and businesses eagerness to move to electronic commerce w:Business-to-business_electronic_commerce

### B2C

Commercial business supplying products or services directly to the consumer. This industry is growing as companies minimize their cost of operation while able to reach a wider group of customer at anytime. An example of B2C is Amazon.com.

#### avoid online shopping rush!

Some leading retail Web sites struggled to keep up with the rush of cybershoppers on Black Friday and Cyber Monday, two of the busiest online shopping days.It took some consumers up to two minutes to process their transactions -- even if they had high-speed Internet connections. It usually only takes one to two seconds to process transactions on a normal day.The worst-performing sites on Black Friday were sometimes four times slower than normal, shoppers experiencing such slowdowns would likely give up and buy the product on another Web site.

### C2C

Consumer-to-consumer system, consumers sell goods or services directly to other consumers.
An example of C2C is Ebay. Ebay was created by Pierre Omidyar is 1995 on his home computer in his living room. It was created so that everyday people would be able to create their own online auction to sell personal items. One major attribute to Ebays succcess is the sites userfriendly interface and lack of complexity.
Two advantages of C2C are reduced costs most of the time, and a smaller but more profitable consumer base. [txt. pg 455]
Disadvantages of C2C is lack of security in safe purchases, lack of quality control and seller is not guaranteed of payment and should not accept payment such as cheques

## reports in business
### Operational for lower management

Used by lower management for day to day operations.

### Tactical for middle management

Report generated for the middle management. Their time frame and goal are usually larger scale and longer than the lower day to day activities. They are specific goals that are to be achieved in an annual or bi quarterly period.

### Strategic for upper management

Top-level management are responsible for making strategic decisions. Reports are generated for upper management to make business wide decisions [Serene's Brain] They give the company a general direction to where the company is heading in a prolong period of time. I.E Ford's agenda might be, reduce cost of production and stay innovative toward environmentally friendly vehicles.

## Information systems
### OIS

Office Information Systems Combines various technologies to reduce manual labor required in operating an efficient office environment. OIS technologies include fax, email, voicemail, word processing, etc.
The main objectives of office information systems are to facilitate communication and collaboration between the members of an organization and to facilitate them between organizations. Placing an organization's documents and messages in an electronic format—which can be classified, indexed, and stored for easy retrieval—enables individuals to access information on demand. One type of office information system, known as a workflow system, is used to route relevant documents automatically to all appropriate individuals for their contribution. Other types of office information systems handle digital messages in the form of electronic mail, facsimile, and voice mail.
Another category of office information systems allows different individuals to work simultaneously on a shared project by using networked computers. Known as groupware, such systems accomplish this by continually sending updated documents—such as business proposals, new designs, or progress reports—to each collaborator's computer. These individuals and their computers need not be located in the same office or even the same building. Groupware is usually deployed over an intranet, a private network that is closed to the general public, and is often accessed by using software originally developed for the Internet. http://www.britannica.com/eb/article-218057/information-system

### TPS

Transaction Processing Systems is when the computer system is used to collect, modify, store, and retrieve the transactions of an organization. The computer must pass the ACID test in order to be considered a TPS. A TPS is used to summarize data. w:Transaction_Processing_System

### MIS

MIS stands for Management information Systems, sometimes referred to as Information Management and Systems. MIS is the process of covering the application of people, technologies, and procedures in order to solve business problems. w:Management_information_systems
They are used to analyze other information systems applied in operational activities in the organization (Therefore used by lower-level managers) w:Management_information_systems

### DSS

A decision support system is a computer-based information system that helps to analyze data and presents it in a form that is understandable by managers or exectutives. In order for an organization to implement DSS technology, they must have already installed TPS and MIS first. DSS should be adaptable, flexible, interactive and be easy to use. The benefit of the DSS should exceed cost. In contrast, while TPS and MIS systems summarize data, a DSS analyzes data.w:Decision_support_system
This is commonly used by middle managers, but should support managers at all levels. There are many varieties of DSS - model driven, communication driven (Microsoft Net Meeting), Data-driven or data-riented, document-driven and knowledge driven.

### ESS

An "easy-to-use" DSS that includes information from outside the company. Executive Support System (ESS) is a reporting tool that allows one to turn a report into a summarized document. This tool is mainly used by company managers. The reports created give summaries for things such as billing, cost accounting, staffing, scheduling, and more.
This is commonly used by upper managers. The ESS is used for strategic decision making: analyzing data and "what if" scenarios.
Benefits of ESS
(http://www.gardler.org/teaching/courses/MIS/DSS/ess.html)

## Privacy

Is the ability to control the information flow in any respect, to either allow, or not, others to view, manipulate or remove private, personal, or confidential materials. w:Privacy

### Name Migration

When you put your name and give it to a company then they sell it to other companies and then you start receiving a bunch of offers from many different places in the mail.

### Resume Rustling

resume posted online looked by third party. This will only occur in open public sites that are not secured by a login ID.

### Government Spying

These are steps taken by the government without the permission of individuals of personal data such as flight information to give the government higher security rank. Its become even more critical since the war on terrorism. for example , computer assisted passenger pre-screening program

### Privacy Laws

Privacy laws are laws that protect individuals for people invading the personal information. It has to be done by weighting the benefits against the cost of reinforcing the laws an example of this is the "freedom of information act in 1970". Governments and many organizations collect personal information for many different purposes. Privacy laws limit how organizations may collect and use different information.
In Canada, the federal Personal Information Protection and Electronic Documents Act governs the collection, use and disclosure of personal information in connection with commercial activities and personal information about employees of federal works, undertakings and businesses.w:Privacy_law
The right of privacy is restricted to individuals who are in a place that a person would reasonably expect to be private (e.g., home, hotel room, telephone booth). (http://en.wikipedia.org/wiki/Privacy_law)

### Identity Theft

Identity Theft is a term for all crimes which involves illegal usage of another individual's identity. The most common form of identity theft is normally credit card fraud. The practice of stealing money or getting benefits while pretending to be a different person has been around since the beginning of time, but Identity Theft is a relatively new term to describe the illegal act. w:Identity_theft
Theft of personal information for fraudulent use. This is a growing concern as more and more data are digitalized.
There are four types of identity theft: 1. Financial Identity Theft 2. Criminal Identity Theft 3. Identity Cloning 4. Business/ Commercial Identity Theft
w:Identity_theft
Identity theft involves stealing, misrepresenting or hijacking the identity of another person or business and provides an effective means to commit other crimes