SQL Server SUM() Function
The SUM() function in SQL Server calculates the sum (total) of numeric values in a column. It's a fundamental aggregate function, used for summarizing numerical data from multiple rows.
SUM(): Definition and Usage
SUM() is incredibly useful for getting totals from your data. It efficiently adds up all the non-null numeric values in the specified column. NULL values are automatically skipped in the summation, ensuring you get a clean total of only the valid numeric data. This function is frequently used for tasks such as calculating total sales, summing quantities, or aggregating other numeric values across a table or a subset of a table.
Syntax
Syntax
SUM(expression)
Parameter Values
| Parameter | Description |
|---|---|
expression |
A numeric column name or a formula that results in a numeric value. This is required. |
Example
Calculating the Total Quantity
This example calculates the total 'Quantity' from the 'OrderDetails' table (assuming a table named 'OrderDetails' exists with a 'Quantity' column). Rows where 'Quantity' is NULL are not included in the sum.
Syntax
SELECT SUM(Quantity) AS TotalItemsOrdered FROM OrderDetails;
Output
TotalItemsOrdered
-----------------
(The sum of all non-null Quantity values from the OrderDetails table will be shown here.)