[Solved] Find the error in this PostgreSQL query:SELECT product_type, COUNT(*) FROM inventory GROUP BY product_type HAVING COUNT(*) < 10 ORDER BY product_type; | PostgreSQL

PostgreSQL - Aggregate Functions and GROUP BY

Find the error in this PostgreSQL query:

SELECT product_type, COUNT(*) FROM inventory GROUP BY product_type HAVING COUNT(*) < 10 ORDER BY product_type;

AHAVING clause should come before GROUP BY.

BNo error; the query is correct.

CORDER BY cannot be used with GROUP BY.

DCOUNT(*) cannot be used in HAVING clause.

Step-by-Step Solution

Solution:

Step 1: Check clause order
Correct order is SELECT, FROM, GROUP BY, HAVING, ORDER BY.
Step 2: Validate HAVING usage
HAVING filters groups using aggregate functions like COUNT(*).
Step 3: Confirm ORDER BY usage
ORDER BY can be used after HAVING to sort results.
Final Answer:
No error; the query is correct. -> Option B
Quick Check:
HAVING filters groups; ORDER BY sorts results [OK]

Quick Trick: HAVING after GROUP BY, ORDER BY last [OK]

Common Mistakes:

Master "Aggregate Functions and GROUP BY" in PostgreSQL

9 interactive learning modes - each teaches the same concept differently

Find the error in this PostgreSQL query: