Are you interested in effectively querying complex data structures in an iterative manner? Do you find yourself working with hierarchical data structures that require efficient querying? This comprehensive course is designed to equip you with the necessary tools and techniques to address these challenges. Throughout the course, you will gain proficiency in writing recursive queries and effectively querying hierarchical data structures. Leveraging the power of Common Table Expressions (CTE) and the recursion principle, you will explore diverse datasets to master these skills. For instance, you will delve into a flight plan dataset, acquiring the ability to identify the optimal and most cost-effective connection between two airports. By the end of this course, you will have a solid understanding of recursion principles and the ability to discern and construct hierarchical data models.