MIS Study Companion
1. What is an Information System (IS)?
Definition:
An Information System is a set of interrelated components that retrieve, process, store,
and distribute information to support decision-making and control in an organization.
Example:
A sales system that records customer orders and generates reports to help managers decide
on inventory needs.
2. Types of Information Systems (OIS - Organizational Information Systems)
System Type Purpose Example
Transaction
Handles daily routine transactions Payroll system,
Processing System
critical to business operations. order processing
(TPS)
Office Automation Supports office workers with document Word processing,
System (OAS) handling and communication. email systems
Knowledge Work Helps knowledge workers create new CAD software for
System (KWS) information. engineers
Management Provides middle managers with reports
Monthly sales
Information System based on TPS data for short-term
report
(MIS) planning.
Helps managers make decisions with
Decision Support Financial
semi-structured data using “what-if”
System (DSS) forecasting tools
analysis.
Supports senior management with
Executive Information Dashboard for CEO
summarized data, often displayed
System (EIS) overview
graphically.
3. Organizational Levels & IS Support
Level Role IS Support Example
Clerical Support managers at all levels Data entry systems
Operational First-line managers (day-to-day) TPS for daily activities
Knowledge-work Expert advisors to management KWS for specialized tasks
Tactical Middle managers (planning/control) MIS for routine reports
Strategic Senior managers (long-term decisions) EIS for overall strategy
4. Data Management Basics
• Data: Raw facts (numbers, text) that by themselves have no meaning.
• Information: Processed data organized meaningfully to support decisions.
Example:
Data: 1001, 2002, 1503 (just numbers)
Information: Sales figures for three products (organized, meaningful)
5. Database and DBMS
• Database: Organized collection of related data stored electronically.
• DBMS (Database Management System): Software that manages databases and
provides an interface for users and applications.
Roles:
• Database Administrator (DBA): Skilled professional who manages database
setup, security, and maintenance.
6. Hierarchy of Data
Level Description Example
Bit Binary digit (0 or 1) 0 or 1
Represents one
Byte 8 bits
character
Character Basic unit of information Letter “A”
Name, number, or characteristic describing an
Field Employee Name, ID
object
Record A collection of related fields (one entity) One employee’s data
File/Table Collection of records Employee table
Database Collection of related tables/files Company HR database
7. Data Entities, Attributes, and Keys
• Entity: Something about which data is stored (e.g., Student, Product,
Employee).
• Attribute: Characteristic of an entity (e.g., Student ID, Employee Name).
• Data Item: Specific value of an attribute (e.g., Student ID = 1001).
Keys:
• Primary Key: Unique identifier for an entity instance (e.g., Employee Number).
• Compound Key: Combination of attributes used as a unique identifier.
• Foreign Key: Attribute in one table that refers to the primary key in another
table.
8. Database Design: Entity-Relationship Model (ERD)
• Diagrammatic tool to model entities and their relationships.
• Helps organize data efficiently and avoid redundancy.
Example:
• Entity: Student
• Entity: Course
• Relationship: Student enrolls in Course (One-to-Many)
9. Database Approach vs File Processing
Aspect File Processing Database Approach
Data Redundancy High, duplicate data stored Low, data normalized
Data Integrity Poor due to duplication Better enforced via DBMS rules
Data Access Limited and inflexible Flexible query capability
Data Security Basic, often manual Built-in access controls
Data Sharing Difficult across departments Easy sharing with permissions
10. SQL and Query Languages
SQL (Structured Query Language): Industry-standard language to extract, modify, and
manage data in relational databases.
Example:
QBE (Query By Example): User-friendly visual query method where users drag and
drop fields to build queries.
11. Reports and Report Generation
• Reports summarize and format data for decision-making.
• Report Generator: Software that creates formatted reports using SQL or other
query languages.
Example:
Monthly sales report showing total sales by region.
12. Database Normalization
• Process to reduce data redundancy and improve data integrity by organizing
tables and relationships correctly.
• Goal: Store data in multiple related tables rather than one large table.
13. Steps to Set Up a Database
1. Consult Users: Identify data needs and reports required by users.
2. List Fields: Collect all data fields required.
3. Determine Relationships: Identify how data fields relate.
4. Create Data Model: Use ER diagrams.
5. Normalize Tables: Organize tables to avoid redundancy.
6. Implement DBMS: Create tables, keys, constraints.
7. Develop Queries and Reports: Based on user needs.
Example Scenario: School Database
• Entities: Students, Courses, Enrollments
• Attributes: Student Name, Course Number, Enrollment Date, Grade
• Relationships: Students enroll in many courses; each course has many
students.
MIS Cheat Sheet
1. Information System (IS)
• Set of components that collect, process, store, distribute info to support
decision making.
2. Types of Information Systems
System Purpose Users
TPS Record daily transactions Operational level
OAS Office document & communication Data workers
KWS Create & integrate knowledge Knowledge workers
MIS Reports for middle management Middle managers
DSS Support decision-making Managers
EIS Support top-level executives Senior management
3. Data Hierarchy
• Bit → Byte → Character → Field → Record → File/Table → Database
4. Database Key Terms
• Entity: Object to store data about (e.g., Student)
• Attribute: Data describing an entity (e.g., Student ID)
• Primary Key: Unique identifier for record (e.g., Employee No.)
• Foreign Key: Links tables (refers to primary key in another table)
5. Database Models
• Relational Model: Tables linked by keys; most common database structure.
• ERD: Diagram showing entities & relationships (One-to-One, One-to-Many)
6. Database Management System (DBMS)
• Software managing databases, providing data retrieval, security, and integrity.
7. SQL Basics
• SELECT — Retrieve data
• JOIN — Combine tables on key fields
• WHERE — Filter records
Example:
8. Normalization
• Organize data to reduce redundancy & improve integrity.
• Store data in multiple related tables instead of one big table.
9. Report Generation
• Reports format data for decision-making.
• Tools: SQL queries, report generators (e.g., Crystal Reports).
10. Database Setup Steps
1. Gather user info needs
2. List all required data fields
3. Identify relationships between data
4. Create data model (ERD)
5. Normalize tables
6. Implement in DBMS
7. Develop queries & reports
