SQL Server SUM() Function

Return the sum of the "Quantity" field in the "OrderDetails" table:

SELECT SUM(Quantity) AS TotalItemsOrdered FROM OrderDetails;

Definition and Usage

The SUM() function calculates the sum of a set of values.

Note: NULL values are ignored.

SUM(expression)

Parameter	Description
expression	Required. A field or a formula

Works in:	SQL Server (starting with 2008), Azure SQL Database, Azure SQL Data Warehouse, Parallel Data Warehouse