SQL SUBQUERY TIPS: - A subquery in SELECT returns a COLUMN. - A subquery in FROM (or JOIN) returns a TABLE. - A subquery in WHERE returns a SINGLE VALUE. Once you understand this, you have ...

📘 Day 17/30 – Subqueries Welcome back to Daily SQL for Data Careers 👋 Today I learned about subqueries. 👉 A subquery is a query inside another query. --- 🔹 Example: SELECT name, salary FROM ...

Correlated subqueries A correlated subquery references a column from the outer query, so it re-executes once for every row the outer query processes. The example below uses a correlated subquery ...

-- Q1: List all employees using an alias for the employees table. -- 2. Subquery using NOT IN -- Q2: Find all employees who are not in any department under the 'Health' division. -- 3. Subquery using ...