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SQL SUM() Function

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The SQL SUM() Function

The SUM() function returns the total sum of a numeric column.

Example

Return the sum of all Quantity fields in the OrderDetails table:

SELECT SUM(Quantity)
FROM OrderDetails;
Try it Yourself »

Syntax

SELECT SUM(column_name)
FROM table_name
WHERE condition;

Demo Database

Below is a selection from the OrderDetails table used in the examples:

OrderDetailID OrderID ProductID Quantity
1 10248 11 12
2 10248 42 10
3 10248 72 5
4 10249 14 9
5 10249 51 40

Add a Where Clause

You can add a WHERE clause to specify conditions:

Example

Return the number of orders made for the product with ProductID 11:

SELECT SUM(Quantity)
FROM OrderDetails
WHERE ProductId = 11;
Try it Yourself »

Use an Alias

Give the summarized column a name by using the AS keyword.

Example

Name the column "total":

SELECT SUM(Quantity) AS total
FROM OrderDetails;
Try it Yourself »

SUM() With an Expression

The parameter inside the SUM() function can also be an expression.

If we assume that each product in the OrderDetails column costs 10 dollars, we can find the total earnings in dollars by multiply each quantity with 10:

Example

Use an expression inside the SUM() function:

SELECT SUM(Quantity * 10)
FROM OrderDetails;
Try it Yourself »

We can also join the OrderDetails table to the Products table to find the actual amount, instead of assuming it is 10 dollars:

Example

Join OrderDetails with Products, and use SUM() to find the total amount:

SELECT SUM(Price * Quantity)
FROM OrderDetails
LEFT JOIN Products ON OrderDetails.ProductID = Products.ProductID;
Try it Yourself »

You will learn more about Joins later in this tutorial.

Test Yourself With Exercises

Exercise:

Use an SQL function to calculate the sum of all the Price column values in the Products table.

SELECT 
FROM Products;

Start the Exercise


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