Learning Objectives

By the end of this lesson, learners should be able to:

  • Define database and DBMS.
  • Explain tables, records, and fields.
  • Distinguish between relational and non-relational databases.
  • Describe primary keys and relationships.
  • Explain data warehouses and structured data storage.

Meaning Of A Database

A database is an organized collection of related data stored electronically for efficient retrieval, updating, and analysis.

A Database Management System (DBMS) is software that enables users to create, manage, query, and secure databases.

Examples include MySQL, PostgreSQL, SQL Server, and Oracle Database.

Tables, Records, And Fields

Component

Meaning

Table

Collection of related data

Record (Row)

One entity instance

Field (Column)

One attribute

Example: Customer Table

CustomerID

hName

Country

1001

Olivia Chen

Singapore

1002

Daniel Smith

Canada

Primary Keys

A primary key uniquely identifies each record.

Benefits:

  • Prevents duplicate records,
  • Supports accurate updates,
  • Enables relationships,
  • Improves data integrity.

Foreign Keys And Relationships

A foreign key links one table to another.

Example:

  • Customer table contains CustomerID.
  • Orders table contains CustomerID.
  • One customer can place many orders.

Relational Databases

Relational databases store data in related tables and support SQL querying.

Advantages

  • Reduced duplication,
  • Improved consistency,
  • Better integrity control,
  • Easier reporting.

Non-Relational Databases

Store flexible or unstructured data such as documents, JSON files, images, and social media content.

Examples: MongoDB, Cassandra.

Data Warehouses

A data warehouse stores integrated historical data for analytics and reporting.

Characteristics:

  • Subject-oriented,
  • Integrated,
  • Time-variant,
  • Non-volatile.

Business Example

A global retail company stores customer, product, and sales data in a centralized data warehouse. Analysts in New York, London, and Singapore access the same trusted data to prepare regional performance reports.

Learning Materials / Reference Materials

  • Coronel & Morris. Database Systems.
  • SQLBolt Tutorials.
  • PostgreSQL Documentation.
  • Oracle Database Concepts Guide.

Lesson Summary

Databases provide organized, secure, and efficient storage of business data. Understanding tables, keys, relationships, and data structures is essential for reliable analytics and reporting.

PreviousNext