Introduction

The COUNT() function in SQL is used to get the total number of rows that match a specified condition. It is very helpful in counting the number of records or rows in a table based on certain criteria.

SQL COUNT() Syntax

The general syntax for the COUNT() function is as follows:

SELECT COUNT(column_name)
FROM table_name
WHERE condition;
            

You can also use COUNT(*) to count all rows in a table.

Examples in SQL

1. Find the Total Number of Rows in the Products Table

Suppose we have a table called Products and we want to count the total number of rows (products) in the table.

SELECT COUNT(*)
FROM Products;
            

2. Count Products with a Specific Column (Non-NULL)

If you want to count how many products have a ProductName listed, excluding null values:

SELECT COUNT(ProductName)
FROM Products;
            

3. Count Products Based on Condition

For example, we want to find the number of products where the price is greater than ₹500:

SELECT COUNT(ProductID)
FROM Products
WHERE Price > 500;
            

4. Count Distinct Values

To count distinct prices (ignoring duplicates), use the DISTINCT keyword:

SELECT COUNT(DISTINCT Price)
FROM Products;
            

5. Count Products Using Group By

To count the number of products in each category, use the GROUP BY clause:

SELECT COUNT(*) AS [Number of Products], CategoryID
FROM Products
GROUP BY CategoryID;