Data, Information, and Knowledge (DIKW Hierarchy)

Study Notes

DIKW Hierarchy

Wisdom is the top of the DIKW hierarchy, requiring answers to questions like 'why do something' and 'what is best'.
Wisdom involves knowledge applied in action.

File System

A file system stores data electronically in files, with each file storing only one table (flat file).
File systems can be stored in physical locations like hard drives, CDs, DVDs, and flash drives.
Benefits of file systems include:
- Easy to implement and understand
- No need for technical staff
- Less skills required
- High processing speed
- Low hardware and software requirements
- Suitable for small databases
Drawbacks of file systems include:
- Less security
- Data inconsistency
- Data and program dependence
- More redundancy
- Limited sharing of information
- Slow searching process
- High complexity when updating
- Difficulty in accessing data

Database Concepts

A database is a collection of interrelated data organized into tables.
A database is an integrated collection of stored operational data used by an enterprise's application systems.
Examples of databases include university databases and library databases.

Database Examples

University database: stores information related to students, courses, and grades.
Library database: records data concerning books, such as titles, authors, and publication details.

Benefits of Database

Stored data
Easy to use
Reduced data redundancy
Reduced complexity
Controlled data inconsistency
Maintained data integrity
Improved data security
Fast searching
Handles large numbers of data
Shared data among users
Easy access to information
Provides backup and recovery

Database Management Systems (DBMS)

Definition: a collection of tools used to create, maintain, and manage databases.
Four basic DBMS functions:
- Create, modify, and remove tables
- Add, modify, and delete data
- Retrieve data selectively
- Generate reports

DBMS Software Types

1. Relational Database Software (e.g., Microsoft Access, Oracle, Sybase, Paradox)
1. Flat-File Database Software (e.g., simple applications like mailing lists or personnel files)

Advantages of DBMS

Sharing of information
Fast response to information requests
Multiple access
Minimized redundancy
Less storage
Accuracy and data integrity
User-friendly
Improved security
Provides backup and recovery

Disadvantages of DBMS

Costly implementation and maintenance
Time-consuming training requirements

Database System Components

1. Data: stored in a single database, shared and integrated.
1. Hardware: physical devices, including processors, main memory, and secondary storage devices.
1. Software: DBMS, operating system software, and application programs.
1. Users: system administrators, database administrators, database designers, system programmers, and end-users.

Database Management System Applications

1. Personal Database Application (Single-User DB Application)
- Characteristics: single-user, small amount of data (<10 MB), simple forms and reports.
1. Multi-User Database Application (Workgroup Database)
- Characteristics: supports multiple users (<50), complex forms and reports, data size <100 MB.
1. Organizational Database Application (Enterprise Database)
- Used by entire organization, supporting many users across departments.

Description

Test your understanding of the Data, Information, Knowledge, and Wisdom (DIKW) hierarchy, including data storage and file systems. Learn how to apply knowledge to achieve goals and make informed decisions.