GROUP BY & Aggregates in SQL
From the SQL cheat sheet · Aggregation · verified Jul 2026
GROUP BY & Aggregates
Summarize data with aggregate functions and grouping.
sql
-- Aggregate functions
SELECT COUNT(*) FROM users;
SELECT SUM(amount) FROM orders;
SELECT AVG(age) FROM users;
SELECT MIN(price), MAX(price) FROM products;
-- GROUP BY
SELECT city, COUNT(*) AS user_count
FROM users
GROUP BY city;
-- HAVING — filter groups
SELECT city, COUNT(*) AS cnt
FROM users
GROUP BY city
HAVING COUNT(*) > 10;💡 WHERE filters rows before grouping; HAVING filters groups after aggregation
⚡ COUNT(*) counts all rows; COUNT(column) counts only non-NULL values
📌 Every non-aggregated column in SELECT must appear in GROUP BY
🟢 Execution order: WHERE → GROUP BY → HAVING → SELECT → ORDER BY → LIMIT
aggregategroup-byhavingcountsum