SQL: Обобщенное табличное выражение (CTE) — как писать сложные запросы просто

When SQL queries become complex, they quickly degenerate into cumbersome constructs with nested subqueries that are difficult to read, debug, and maintain. Common Table Expressions (CTEs) allow you to break queries into logical steps, making code clear and reusable, and simplifying work with complex business logic. In this webinar, we'll explore how to use CTEs in real-world scenarios, how they differ from subqueries, and how to use them to write SQL as a sequential pipeline. In this webinar, we'll discuss: What is a common table expression (CTE) and why is it needed? The difference between CTEs and nested subqueries How to break a complex query into steps Using multiple CTEs in a single query CTEs in SELECT, UPDATE, and DELETE Recursive CTEs: Working with hierarchies and sequences Optimization features and their impact on query execution After this webinar, you'll be able to: Write complex SQL queries in a structured and understandable manner Break logic into steps and simplify code maintenance Use CTEs instead of cumbersome subqueries Apply recursive CTEs to work with hierarchies Use CTEs consciously, considering performance Target audience: Developers, analysts, and data scientists who already know how to write SELECT, JOIN, and GROUP BY statements and want to learn how to structure complex queries and make them readable and supported. "PostgreSQL for Database Administrators and Developers" - https://otus.pw/dToD/ Instructor: Anastasia Chekushina - Senior SQL Developer | Educator at Maxim Technology Take the survey following the event - https://otus.pw/ViAh/ Follow the project news: → VK: https://vk.com/otusru → Telegram: https://t.me/Otusjava → Habr: https://otus.pw/S0nM/ → Max: https://otus.pw/wVga/