Subqueries vs. CTEs and When to Use Each

SQL offers multiple ways to break down complex problems into manageable steps. Two of the most powerful tools for this are subqueries and Common Table Expressions (CTEs). While they often overlap in functionality, understanding their differences is key to writing efficient, maintainable queries. A subquery is a query nested inside another query. It executes first, and its result feeds into the outer query. Subqueries can appear in SELECT , FROM , or WHERE clauses. Example: SELECT first_name FROM