Day -1 :Mastering Subqueries in PostgreSQL: Unleashing Advanced Techniques

Follow for content on Investing : LinkedIn / Instagram

Follow for content on Technical: LinkedIn

Photo by Matheus Bertelli: https://www.pexels.com/photo/a-computer-monitor-with-keyboard-and-mouse-on-the-table-7031697/

Introduction: Elevating Your Subquery Skills

In the world of PostgreSQL, mastering subqueries is like unlocking a treasure chest of advanced querying capabilities. In this guide, we’ll journey beyond the basics and dive into advanced subquery techniques that will empower you to tackle complex data challenges with confidence.

Section 1: Correlated Subqueries Revisited

Correlated subqueries are a potent tool when you need to reference values from the outer query within the subquery. Let’s revisit this concept with more advanced scenarios. Consider a case where you want to find employees whose salaries are higher than the average salary within their respective departments.

Section 2: Subqueries in the FROM Clause (Derived Tables)

Subqueries aren’t limited to the WHERE clause. You can use them in the FROM clause to…