The SQL COUNT(), AVG() and SUM() Functions
The SQL COUNT(), AVG() and SUM() Functions
The COUNT() function returns the number of rows that matches a specified criterion.
The AVG() function returns the average value of a numeric column.
The SUM() function returns the total sum of a numeric column.
COUNT() Syntax
SELECT COUNT(column_name)
FROM table_name
WHERE condition;
AVG() Syntax
SELECT AVG(column_name)
FROM table_name
WHERE condition;
SUM() Syntax
SELECT SUM(column_name)
FROM table_name
WHERE condition;
COUNT() Example
The following SQL statement finds the number of products:
Example
SELECT COUNT(ProductID)
FROM Products;
AVG() Example
The following SQL statement finds the average price of all products:
Example
SELECT AVG(Price)
FROM Products;
SUM() Example
The following SQL statement finds the sum of the "Quantity" fields in the "OrderDetails" table:
Example
SELECT SUM(Quantity)
FROM OrderDetails;
