Unit 01

Q1) Write short note on: Operational support system

Operational systems are computer-based systems designed to manage the day-to-day transactions and operations of an organization. They are application-oriented and mainly used to run the business rather than analyze it. These systems store detailed and current data, usually in an isolated form, and are optimized for known transactions and workloads. Examples include university record systems, inventory management, claims processing, and billing systems.

They are performance-sensitive, providing quick responses for repetitive tasks and supporting only a few records accessed at a time. The primary users are clerical staff, and access is generally for reading or updating records. Operational systems are not suitable for providing strategic information because they are not designed for large-scale data analysis, integration, or decision support, but rather for ensuring smooth, accurate, and efficient daily operations.

Q2) Data Warehouse and its Characteristics

A Data Warehouse is a subject-oriented, integrated, time-variant, and non-volatile collection of data used to support management’s decision-making process. It stores large volumes of historical data collected from various sources, which is then cleaned, transformed, and organized for analysis. The concept was defined by Bill Inmon in 1990, and it enables organizations to make strategic business decisions by providing a consistent and consolidated view of data.

Characteristics of a Data Warehouse:

1. Subject-Oriented – Focuses on specific subjects (e.g., sales, customers) rather than day-to-day operations.
2. Integrated – Combines data from multiple heterogeneous sources into a coherent, consistent format.
3. Non-Volatile – Once data is stored, it is not changed or deleted; it remains stable for analysis.
4. Time-Variant – Stores historical data over a long period, allowing trend analysis and comparisons over time.

This structure allows decision-makers to perform complex queries, analyze trends, and gain valuable insights for long-term planning.

Q3) Data Warehouse Architecture and Data Warehouse vs Data Mart

The data warehouse architecture consists of three main systems:

1. Source Systems – Operational systems of the organization and external data sources that provide raw data.
2. Data Staging Area – Intermediate storage where data is extracted, transformed, and loaded (ETL). This stage involves cleaning, combining, and preparing data.
3. Presentation Servers – Store organized and processed data for direct querying by end users, report writers, and applications.