Databases 1 - JSS3 Computer Studies Past Questions and Answers - page 2

The relational database model organizes data into tables with rows and columns, providing a two-dimensional structure. It uses a set of mathematical principles and offers flexibility, scalability, and efficiency. The model allows for easy navigation and establishes relationships between tables using primary and foreign keys, ensuring data integrity.

A primary key is a unique identifier for each record in a relational database. It serves the purpose of ensuring the uniqueness of each record, preventing duplication and ensuring data integrity. The primary key is used for efficient data retrieval and management, acting as a reference point for establishing relationships with other tables.

The hierarchical model organizes data in a tree-like structure with a top-down hierarchy, suitable for one-to-many relationships. In contrast, the network model represents data as a collection of records connected by various relationships, allowing for more flexibility, including many-to-many connections. The hierarchical model is rigid, while the network model is more complex but offers greater versatility in data organization.