Database Design and SQL SELECT Queries: Messenger Application Case Study

Designing relational databases and extracting insights using SQL queries are essential skills for modern software development and data analysis. This text-based course guides you through foundational database architecture and practical query techniques using a messaging app schema as a structured model. You will begin by building a solid grounding in relational terminology, data types, and primary-foreign key relationships before constructing queries. What you will learn: Understand fundamental database concepts, entity modeling, and relational constraints; Design a structured schema for users, messages, chat groups, and media attachments; Write SELECT queries using WHERE filtering, ORDER BY sorting, and aggregate functions; Combine data across multiple tables using INNER JOIN, LEFT JOIN, and subqueries; Apply modern database practices including index fundamentals and data integrity rules. The course starts with detailed written explanations of core concepts and standard syntax, then guides you step-by-step through querying your newly designed database. This course is created for complete beginners with no prior SQL or programming background. Start reading today to master relational database design and write SQL queries with confidence.