Subqueries in SQL: From Basics to Real-World Scenarios (Data Analytics Training) скачать в хорошем качестве

Subqueries in SQL: From Basics to Real-World Scenarios (Data Analytics Training)

Welcome to the latest session of our Data Analytics Training series! In this class, we dive deep into SQL subqueries, covering how and why to use them, performance considerations, and practical examples you can apply right away. What you’ll learn: What subqueries are and where they fit in SQL Step-by-step examples of scalar, row, and correlated subqueries Best practices for readability and maintenance How to optimize subqueries for better query performance Real-world scenarios and hands-on exercises you can replicate Key topics with examples: Simple scalar subquery: comparing values with a subquery Subqueries in the SELECT, FROM, and WHERE clauses Correlated subqueries: referencing outer queries Using EXISTS and IN with subqueries Common pitfalls and how to avoid them Why this matters: Build more powerful queries to answer complex data questions Improve data extraction workflows in analytics projects Prepare for advanced SQL tasks in interviews and real-world roles If you enjoy this session, please: Like and share with peers who are learning SQL Subscribe for more data analytics tutorials and live Q&A sessions Comment below with topics you’d like to see next or any questions you have about subqueries Chapters (timestamps): 0:00 Introduction 1:15 What are subqueries? 5:40 Scalar subqueries 9:20 Subqueries in SELECT, FROM, WHERE 14:05 Correlated subqueries 18:30 EXISTS vs IN 22:45 Common pitfalls 26:10 Real-world examples 30:00 Q&A and wrap-up FAQ and tips: If you’re using a specific SQL flavor, note in the comments which one you’re working with. For practice, try rewriting your own queries using subqueries to answer a business question you’re analyzing. SQL subqueries, SQL subquery tutorial, data analytics training, SQL queries, advanced SQL, database querying, subquery examples #sql-subqueries-tutorial #data-analytics-training #advanced-sql-examples