MySQL HAVING Clause

The HAVING clause filters the results after GROUP BY has formed its groups. It is the equivalent of WHERE, but for grouped data. While WHERE cannot reference aggregate functions like COUNT() or SUM(), HAVING can — because by the time HAVING runs, the groups and their aggregates have already been calculated.

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HAVING vs WHERE — The Key Difference

Clause	Filters	Can use aggregate functions?
WHERE	Individual rows before grouping	No
HAVING	Groups after grouping	Yes

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Syntax

SELECT column, aggregate_function(column)
FROM table_name
WHERE condition
GROUP BY column
HAVING aggregate_condition
ORDER BY column;

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Sample Table

id	name	category	price	quantity_sold
1	Laptop	Electronics	55000.00	5
2	Phone	Electronics	25000.00	12
3	T-Shirt	Clothing	800.00	40
4	Headphones	Electronics	3500.00	18
5	Jeans	Clothing	2200.00	22
6	Tablet	Electronics	35000.00	8
7	Jacket	Clothing	4500.00	15

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HAVING with COUNT()

Show only categories that contain more than 3 products:

SELECT category, COUNT(*) AS total
FROM products
GROUP BY category
HAVING COUNT(*) > 3;

category	total
Electronics	4

Clothing has only 3 products, so it is excluded. Electronics has 4 and passes the filter.

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HAVING with SUM()

Show only categories where the total units sold exceed 50:

SELECT category, SUM(quantity_sold) AS total_sold
FROM products
GROUP BY category
HAVING SUM(quantity_sold) > 50;

category	total_sold
Clothing	77

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HAVING with AVG()

Find categories where the average price is above 10,000:

SELECT category, ROUND(AVG(price), 2) AS avg_price
FROM products
GROUP BY category
HAVING AVG(price) > 10000;

category	avg_price
Electronics	29625.00

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Combining WHERE and HAVING

Use both in the same query: WHERE filters individual rows first, then GROUP BY forms groups, and finally HAVING filters those groups:

-- Among products priced above 1000 only,
-- show categories with more than 2 such products
SELECT category, COUNT(*) AS total
FROM products
WHERE price > 1000
GROUP BY category
HAVING COUNT(*) > 2;

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HAVING with AND / OR

You can combine multiple conditions in HAVING using AND and OR:

-- Categories with more than 2 products AND average price above 5000
SELECT category, COUNT(*) AS total, ROUND(AVG(price), 2) AS avg_price
FROM products
GROUP BY category
HAVING COUNT(*) > 2 AND AVG(price) > 5000;

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Key Points to Remember

• HAVING filters groups after GROUP BY — it is the post-grouping equivalent of WHERE.
• WHERE cannot use aggregate functions; HAVING can.
• You can use both WHERE and HAVING in the same query — they serve different stages.
• Execution order: WHERE (rows) → GROUP BY (groups) → HAVING (filter groups) → ORDER BY.
• Combine multiple conditions in HAVING using AND and OR.