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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

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 »

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 »

Unfortunately the Products table does not have any NULL values, but we can fix that. Run the SQL statement below, and re-run the example above to see the result.

Example

Insert a NULL value to better understand the example above:

UPDATE Products
SET ProductName = NULL
WHERE ProductName = 'Chang';
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 »

Test Yourself With Exercises

Exercise:

Use the correct function to return the number of records that have the Price value set to 18.

SELECT (*)
FROM Products
 Price = 18;

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