[Solved] Consider the table orders with columns country, category, and sales. What rows will the following query return?SELECT country, category, SUM(sales) FROM orders GROUP BY CUBE(country, category); | PostgreSQL

PostgreSQL - Aggregate Functions and GROUP BY

Consider the table orders with columns country, category, and sales. What rows will the following query return?

SELECT country, category, SUM(sales) FROM orders GROUP BY CUBE(country, category);

ARows for each country-category pair, plus subtotals for each country, each category, and a grand total.

BRows only for each country-category pair without any subtotals.

CRows for each country and category separately but no grand total.

DRows grouped by country only, ignoring category.

Step-by-Step Solution

Solution:

Step 1: Understand CUBE behavior
CUBE generates all combinations of grouping columns, including individual columns and grand total.
Step 2: Analyze the query
The query groups by CUBE(country, category), so it returns rows for each country-category pair, subtotals by country, subtotals by category, and a grand total row.
Final Answer:
Rows for each country-category pair, plus subtotals for each country, each category, and a grand total. -> Option A
Quick Check:
CUBE returns all grouping combinations including grand total [OK]

Quick Trick: CUBE returns all grouping combinations including grand total [OK]

Common Mistakes:

Master "Aggregate Functions and GROUP BY" in PostgreSQL

9 interactive learning modes - each teaches the same concept differently

Consider the table orders with columns country, category, and sales. What rows will the following query return?