Why does combining multiple aggregate functions in a single SQL query require careful use of GROUP BY and filtering clauses?

hard📝 Conceptual Q10 of 15

SQL - Aggregate Functions

ABecause aggregates summarize data and GROUP BY defines grouping, filtering affects which rows are included

BBecause aggregates can only be used with ORDER BY clause

CBecause GROUP BY automatically filters rows without WHERE

DBecause filtering clauses cannot be used with aggregates

Step-by-Step Solution

Solution:

Step 1: Understand aggregates summarize data
Aggregates like SUM, COUNT summarize rows, so grouping controls how rows are combined.
Step 2: Filtering affects which rows are included
WHERE filters rows before aggregation; HAVING filters groups after aggregation.
Final Answer:
Because aggregates summarize data and GROUP BY defines grouping, filtering affects which rows are included -> Option A
Quick Check:
Aggregates + GROUP BY + filtering control summary results [OK]

Quick Trick: GROUP BY groups; WHERE/HAVING filter rows/groups for aggregates [OK]

Common Mistakes:

MISTAKES

Master "Aggregate Functions" in SQL

9 interactive learning modes - each teaches the same concept differently

Want More Practice?

15+ quiz questions · All difficulty levels · Free

More SQL Quizzes