SUM (Transact-SQL)
Returns the sum of all the values, or only the DISTINCT values, in the expression. SUM can be used with numeric columns only. Null values are ignored. May be followed by the OVER Clause (Transact-SQL).
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Transact-SQL Syntax Conventions
Składnia
SUM ( [ ALL | DISTINCT ] expression )
Arguments
ALL
Applies the aggregate function to all values. ALL is the default.DISTINCT
Specifies that SUM return the sum of unique values.expression
Is a constant, column, or function, and any combination of arithmetic, bitwise, and string operators. expression is an expression of the exact numeric or approximate numeric data type category, except for the bit data type. Aggregate functions and subqueries are not permitted. For more information, see Expressions (Transact-SQL).
Return Types
Returns the summation of all expression values in the most precise expression data type.
Expression result |
Return type |
|---|---|
tinyint |
int |
smallint |
int |
int |
int |
bigint |
bigint |
decimal category (p, s) |
decimal(38, s) |
money and smallmoney category |
money |
float and real category |
float |
Examples
A. Using SUM to return summary data
The following examples shows using the SUM function to return summary data.
USE AdventureWorks2012;
GO
SELECT Color, SUM(ListPrice), SUM(StandardCost)
FROM Production.Product
WHERE Color IS NOT NULL
AND ListPrice != 0.00
AND Name LIKE 'Mountain%'
GROUP BY Color
ORDER BY Color;
GO
Here is the result set.
Color
--------------- --------------------- ---------------------
Black 27404.84 5214.9616
Silver 26462.84 14665.6792
White 19.00 6.7926
(3 row(s) affected)
B. Using the OVER clause
The following example uses the SUM function with the OVER clause to provide a cumulative total of yearly sales for each territory in the Sales.SalesPerson table. The data is partitioned by TerritoryID and logically ordered by SalesYTD. This means that the SUM function is computed for each territory based on the sales year. Notice that for TerritoryID 1, there are two rows for sales year 2005 representing the two sales people with sales that year. The cumulative sales for these two rows is computed and then the third row representing sales for the year 2006 is included in the computation.
USE AdventureWorks2012;
GO
SELECT BusinessEntityID, TerritoryID
,DATEPART(yy,ModifiedDate) AS SalesYear
,CONVERT(varchar(20),SalesYTD,1) AS SalesYTD
,CONVERT(varchar(20),AVG(SalesYTD) OVER (PARTITION BY TerritoryID
ORDER BY DATEPART(yy,ModifiedDate)
),1) AS MovingAvg
,CONVERT(varchar(20),SUM(SalesYTD) OVER (PARTITION BY TerritoryID
ORDER BY DATEPART(yy,ModifiedDate)
),1) AS CumulativeTotal
FROM Sales.SalesPerson
WHERE TerritoryID IS NULL OR TerritoryID < 5
ORDER BY TerritoryID,SalesYear;
Here is the result set.
BusinessEntityID TerritoryID SalesYear SalesYTD MovingAvg CumulativeTotal
---------------- ----------- ----------- -------------------- -------------------- --------------------
274 NULL 2005 559,697.56 559,697.56 559,697.56
287 NULL 2006 519,905.93 539,801.75 1,079,603.50
285 NULL 2007 172,524.45 417,375.98 1,252,127.95
283 1 2005 1,573,012.94 1,462,795.04 2,925,590.07
280 1 2005 1,352,577.13 1,462,795.04 2,925,590.07
284 1 2006 1,576,562.20 1,500,717.42 4,502,152.27
275 2 2005 3,763,178.18 3,763,178.18 3,763,178.18
277 3 2005 3,189,418.37 3,189,418.37 3,189,418.37
276 4 2005 4,251,368.55 3,354,952.08 6,709,904.17
281 4 2005 2,458,535.62 3,354,952.08 6,709,904.17
(10 row(s) affected)
In this example, the OVER clause does not include PARTITION BY. This means that the function will be applied to all rows returned by the query. The ORDER BY clause specified in the OVER clause determines the logical order to which the SUM function is applied. The query returns a cumulative total of sales by year for all sales territories specified in the WHERE clause. The ORDER BY clause specified in the SELECT statement determines the order in which the rows of the query are displayed.
SELECT BusinessEntityID, TerritoryID
,DATEPART(yy,ModifiedDate) AS SalesYear
,CONVERT(varchar(20),SalesYTD,1) AS SalesYTD
,CONVERT(varchar(20),AVG(SalesYTD) OVER (ORDER BY DATEPART(yy,ModifiedDate)
),1) AS MovingAvg
,CONVERT(varchar(20),SUM(SalesYTD) OVER (ORDER BY DATEPART(yy,ModifiedDate)
),1) AS CumulativeTotal
FROM Sales.SalesPerson
WHERE TerritoryID IS NULL OR TerritoryID < 5
ORDER BY SalesYear;
Here is the result set.
BusinessEntityID TerritoryID SalesYear SalesYTD MovingAvg CumulativeTotal
---------------- ----------- ----------- -------------------- -------------------- --------------------
274 NULL 2005 559,697.56 2,449,684.05 17,147,788.35
275 2 2005 3,763,178.18 2,449,684.05 17,147,788.35
276 4 2005 4,251,368.55 2,449,684.05 17,147,788.35
277 3 2005 3,189,418.37 2,449,684.05 17,147,788.35
280 1 2005 1,352,577.13 2,449,684.05 17,147,788.35
281 4 2005 2,458,535.62 2,449,684.05 17,147,788.35
283 1 2005 1,573,012.94 2,449,684.05 17,147,788.35
284 1 2006 1,576,562.20 2,138,250.72 19,244,256.47
287 NULL 2006 519,905.93 2,138,250.72 19,244,256.47
285 NULL 2007 172,524.45 1,941,678.09 19,416,780.93
(10 row(s) affected)