[Solved] Find the problem in this query:SELECT department, product, SUM(sales) FROM sales_data GROUP BY GROUPING SETS ((department, product), (department)); | PostgreSQL

PostgreSQL - Aggregate Functions and GROUP BY

Find the problem in this query:

SELECT department, product, SUM(sales) FROM sales_data GROUP BY GROUPING SETS ((department, product), (department));

ASUM() cannot be used with multiple grouping sets

BThe query is valid and will run without errors

CGROUPING SETS cannot have overlapping grouping sets

DGROUP BY must include all columns in SELECT

Step-by-Step Solution

Solution:

Step 1: Review GROUPING SETS usage
GROUPING SETS can include overlapping sets like (department, product) and (department).
Step 2: Check aggregation and SELECT columns
SUM() is valid, and SELECT columns match grouping sets.
Final Answer:
The query is valid and will run without errors -> Option B
Quick Check:
Overlapping grouping sets are allowed in GROUPING SETS [OK]

Quick Trick: GROUPING SETS can include overlapping column sets [OK]

Common Mistakes:

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