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SQL COUNT() Function

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The SQL COUNT() Function

The COUNT() function returns the number of rows that matches a specified criterion.

Example

Find the total number of products in the Products table:

SELECT COUNT(*)
FROM Products;
Try it Yourself »

Syntax

SELECT COUNT(column_name)
FROM table_name
WHERE condition;

Demo Database

Below is a selection from the Products table used in the examples:

ProductID ProductName SupplierID CategoryID Unit Price
1 Chais 1 1 10 boxes x 20 bags 18
2 Chang 1 1 24 - 12 oz bottles 19
3 Aniseed Syrup 1 2 12 - 550 ml bottles 10
4 Chef Anton's Cajun Seasoning 2 2 48 - 6 oz jars 22
5 Chef Anton's Gumbo Mix 2 2 36 boxes 21.35

Specify Column

You can specify a column name instead of the asterix symbol (*).

If you specify a column instead of (*), NULL values will not be counted.

Example

Find the number of products where the ProductName is not null:

SELECT COUNT(ProductName)
FROM Products;
Try it Yourself »

Add a Where Clause

You can add a WHERE clause to specify conditions:

Example

Find the number of products where Price is higher than 20:

SELECT COUNT(ProductID)
FROM Products
WHERE Price > 20;
Try it Yourself »

Ignore Duplicates

You can ignore duplicates by using the DISTINCT keyword in the COUNT function.

If DISTINCT is specified, rows with the same value for the specified column will be counted as one.

Example

How many different prices are there in the Products table:

SELECT COUNT(DISTINCT Price)
FROM Products;
Try it Yourself »

Use an Alias

Give the counted column a name by using the AS keyword.

Example

Name the column "number of records":

SELECT COUNT(*) AS [number of records]
FROM Products;
Try it Yourself »

Use COUNT() with GROUP BY

Here we use the COUNT() function and the GROUP BY clause, to return the number of records for each category in the Products table:

Example

SELECT COUNT(*) AS [Number of records], CategoryID
FROM Products
GROUP BY CategoryID;
Try it Yourself »

You will learn more about the GROUP BY clause later in this tutorial.

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