Intermediate SQL: Subqueries, CASE Logic, and Query Design

Ready to move beyond basic SELECT statements and simple joins? To solve real-world data problems, you need to write queries that can make decisions, manipulate text, and dynamically pull data from multiple layers. This course guides you through the transition from basic querying to structured, logical database analysis. You will learn how to inject conditional logic directly into your queries, manipulate text strings with precision, and nest queries to solve complex data questions. You will also adopt modern SQL best practices, including Common Table Expressions (CTEs), to keep your code readable and highly performant. What you'll learn: - Apply conditional if-else logic inside your queries using CASE statements. - Extract and format text data dynamically using advanced string functions. - Construct nested subqueries to retrieve deep data insights across tables. - Write clean, readable query structures using Common Table Expressions (CTEs). - Understand how database engines execute queries to write more efficient SQL. You will start by exploring foundational logical concepts and string functions before moving into subqueries and structural query design. Through clear written explanations and practical query exercises, you will build a robust mental model for solving complex data retrieval challenges. This course is designed for learners who already know basic SQL syntax (SELECT, FROM, WHERE, and basic JOINs) and want to elevate their data analysis skills. No advanced programming experience is required. Start writing smarter, more powerful SQL queries today.