Wednesday 22 May 2013

Database Systems, Data Centers and Business Intelligence.

Why learn about database systems, data centers and business intelligence?

Database is an organized collection of data. Database Management System (DBMS) is a group of programs that manipulate the database. Besides that, it is also provide an interface between the database and its users and other application programs. 

Without data and the ability to process the data, an organization could not successfully complete most business activities. Data consists of raw facts. To transform data into useful information, it must first be organized in a meaningful way.

Hierarchy of Data
  • Bit - a binary digit
  • Byte - typically made up of eight bits
  • Character - basic building block of information
  • Field - name, number, or combination of characters that describes an aspect of a business object or activity
  • Record - collection of related data fields
  • File - collection of related records
  • Database - collection of integrated and related files


Data Entities, Attributes and Keys.

Entity - general class of people, places, or things(objects) for which data is collected, stored and maintained.
Attribute - characteristics of an entity
Data Item - specific value of an attribute
Keys - field or set of fields in a record that is used to identify the record
Primary key - field or set of fields that uniquely identifies the record


The Database Approach

  •  Traditional approach to data management: - Each distinct operational system used data files dedicated to that system
  • Database approach to data management: - Pool of related data is shared by multiple application programs

The Relational Database Model

The relational model describes data using a standard tabular format. Each row of a table represents a data entity or record. The columns of the table represent attributes or fields.

Relational database model also about manipulating data with some process which are:

  • Selecting    - Eliminates rows according to certain criteria
  • Projecting  - Eliminates columns in a table
  • Joining       - Combines two or more tables
  • Linking      - Manipulating two or more tables that share at least one common data attribute 


Database Management Systems (DBMS)

DBMS is about crating and implementing the right database system which ensure that the database will support both business activities and goals.

Data Warehouses, Data Marts, and Data Mining



  • Data warehouse : Database that holds business information from many sources in the enterprise
  • Data mart          : Subset of a data warehouse
  • Data mining       : Information-analysis tool that involves the automated discovery of patterns and relationships in a data warehouse




This is the video which can make you understand more about database :)





Hardware and Software

Why should we learn about software and hardware?

Most organizations use computer hardware to  improve worker productivity, increase the revenue and reduce costs plus to provide better customer service.

There are three main components of computer hardware.
  1. Central Processing Unit (CPU) that contain arithmetic or logic unit, the control unit and the register areas.
  2. Arithmetic/Logic unit (ALU) which performs mathematical calculations and makes logical comparisons
  3. ALU
  4. Control unit who sequentially accesses program instructions, decodes them, and coordinates the flow of data in and out of the ALU, registers, primary storage, and even secondary storage and various output devices.

Processing and Memory devices.

Processing Characteristics and Functions.
  • Clock speed - series of electronic pulses produced at a predetermined rate that effects machine cycle time. Its often measured in Megahertz(MHz) and Gigahertz(GHz)
  • Physical characteristics of the CPU - most CPUs are collection of digital circuits imprinted on silicon wafers, or chip which are smaller than the tip of a pencil eraser.
Memory Characteristics and Functions.
  • Memory - provides the CPU with a working storage area for programs and data. It is rapidly provides data and instructions to the CPU
  • Storage capacity - eight bits together form a byte (B)
  • Types of memory - Random access memory (RAM) and Read-only memory(ROM)
Multiprocessing

Multiprocessing is a simultaneous execution of two or more instructions at the same time. Multicore microprocessor which combines two or more independent processors into a single computer. There are two types of computing which are the parallel and grid computing. Parallel computing is a simultaneous execution of the same task on multiple processors to obtain results faster. Whereas, grid computing is a use of a collection of computers to work in a coordinated manner to solve a common problem.

Secondary Storage and Input Output Devices

Secondary storage offers more advantages of non-volatility, greater capacity and greater company. The devices for the secondary storage are:
- magnetic tapes,
- magnetic disks,
- redundant array of independent/inexpensive disks(RAID),
- virtual tap,
- storage area network,
- optical discs,
- digital video disc(DVD) and
- the solid state secondary storage devices.

The disadvantages of secondary storage devices are cost high per GB of data storage and have lower capacity compared to current hard drives.

Input Devices

There are various of devices used to input general types of data. For example, digital cameras, pen input devices, magnetic stripe card and many more.

Output Devices

The output devices used to display the output from the computer. Example of the output devices are plasma display, LCD displays, digital audio player, e-books and many more.



Computer System Types

Computer systems can range from the desktop portable computers to massive supercomputers that require housing in large rooms. Examples of portable computers are handled computers, laptop computer, notebook computers, tablet computers, smartphone.

Software

Software is a computer programs that contain sequences of instructions for the computers. Every software must have a documentation that describes programs functions to help the user operate the computer system. There are two types of software which are systems software and application software.

Systems software includes the operating systems and utility programs. Operating systems is a set of programs that controls computer hardware and acts as an interface with application programs. Examples of operating systems are Microsoft PC, Apple and Linux. Utility programs is a program that help to perform maintenance or correct problems with a computer system. Besides that, utility programs also can help to secure and safeguard data.

Application software is a type software that can interact the user with the systems software. It also help the user perform common tasks such as creating  and formatting text documents, performing calculations and managing information.

This is a video that may help to understand more about software:



So, this is another videos explain about hardware: 


HAVE A NICE DAY THEN :)

Introduction to Information Systems

Information System

Information System(IS) is the collection of technical and human resources that provide the storage, computing, distribution, and communication for the information required by all or some part of an enterprise. A special form of IS is a management information system (MIS), which provides information for managing an enterprise.

What are the differences between Data, Information and Knowledge?

Data is raw facts or unorganized form such as alphanumeric data, image data, audio data and video data.

Information is a collection of facts organized in such a way that it have a value beyond the facts themselves.

Process is a set of logically related tasks.

Knowledge is the awareness and understanding of a set of information.

The process of Transforming Data into Information

The value of Information are: 
  • directly linked to how it helps decision makers achieve their organization's goals
  • valuable information which can help people and their organizations perform tasks more efficiently and effectively.
What is an Information System?

Information system(IS) is a set of interrelated elements that:
  • collect input
  • manipulate process
  • store
  • disseminate the output such as data and information
  • provide a corrective reaction to meet an objective
The components of an Information System


Input              : Activity of gathering and capturing raw data
Processing  : Converting data into useful outputs
Output          : Production of useful information, usually in the form of documents and reports
Feedback    : Information from the system that is used to make changes to input or processing activities 

Computer-Based Information Systems (CBIS)

  1. Hardware: Consists of computer equipment used to perform input, processing, and output activities
  2. Software: Consists of the computer programs that govern the operation of the computer
  3. Database: Organized collection of facts and information, typically consisting of two or more related data files
  4. Telecommunications, networks, and the Internet: The electronic transmission of signals for communications
  5.  Networks: Connect computers and equipment to enable electronic communication
  6. Internet: World’s largest computer network, consisting of  thousands of interconnected networks, all freely exchanging information
  7. Intranet: Internal network that allows people within an organization to exchange information and work on projects
  8. Extranet: Network that allows selected outsiders, such as business partners and customers, to access authorized resources of a company’s intranet
  9. People: The most important element in most computer based information systems
  10. Procedures: Include strategies, policies, methods, and rules for using the CBIS


Business Information Systems

Business IS is the most common types of information systems those designed for electronic and mobile commerce, transaction processing, management information, and decision support.


Electronic and Mobile Commerce

  • Electronic commerce (e-commerce)
  • Mobile commerce (m-commerce)
  • Electronic business (e-business)

For further more explanation, please do visit my next post then :)