[Solved] What will this query return?SELECT product_name FROM products WHERE price < (SELECT AVG(price) FROM products); | PostgreSQL

PostgreSQL - Subqueries in PostgreSQL

What will this query return?

SELECT product_name FROM products WHERE price < (SELECT AVG(price) FROM products);

AProducts priced below the average price

BProducts priced above the average price

CAll products regardless of price

DError because AVG cannot be used in subquery

Step-by-Step Solution

Solution:

Step 1: Calculate average price using subquery
The subquery returns the average price of all products.
Step 2: Filter products with price less than average
Main query selects products cheaper than this average.
Final Answer:
Products priced below the average price -> Option A
Quick Check:
Subquery calculates average, main query filters below it [OK]

Quick Trick: Use subqueries to compare values against aggregates like AVG [OK]

Common Mistakes:

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What will this query return?