Step-by-Step Guide to Designing a Relational Database for E-commerce Apps

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A BCA student has published a practical tutorial on designing a relational database schema for a basic e-commerce application using SQL. The guide identifies four core entities — Users, Products, Orders, and Order Items — and explains how to structure each as a relational table. Key database concepts covered include primary keys, foreign keys, CHECK constraints, and junction tables to handle many-to-many relationships. A notable design tip highlighted is storing price_at_purchase in the Order Items table to preserve accurate transaction history even if product prices change later. The tutorial aims to bridge the gap between academic DBMS theory and real-world application development.

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