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title: "VAR (Transact-SQL) | Microsoft Docs"
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# VAR (Transact-SQL)
[!INCLUDE[tsql-appliesto-ss2008-all_md](../../includes/tsql-appliesto-ss2008-all-md.md)]

  Returns the statistical variance of all values in the specified expression. May be followed by the [OVER clause](../../t-sql/queries/select-over-clause-transact-sql.md).  
  
 ![Topic link icon](../../database-engine/configure-windows/media/topic-link.gif "Topic link icon") [Transact-SQL Syntax Conventions](../../t-sql/language-elements/transact-sql-syntax-conventions-transact-sql.md)  
  
## Syntax  
  
```  
-- Syntax for SQL Server and Azure SQL Database  
  
VAR ( [ ALL | DISTINCT ] expression )   
   OVER ( [ partition_by_clause ] order_by_clause )    
```  
  
```  
-- Syntax for Azure SQL Data Warehouse and Parallel Data Warehouse  
  
-- Aggregate Function Syntax   
VAR ( [ ALL | DISTINCT ] expression )  
  
-- Analytic Function Syntax  
VAR (expression) OVER ( [ partition_by_clause ] order_by_clause)  
```  
  
## Arguments  
 **ALL**  
 Applies the function to all values. ALL is the default.  
  
 DISTINCT  
 Specifies that each unique value is considered.  
  
 *expression*  
 Is an [expression](../../t-sql/language-elements/expressions-transact-sql.md) of the exact numeric or approximate numeric data type category, except for the **bit** data type. Aggregate functions and subqueries are not permitted.  
  
 OVER **(** [ *partition_by_clause* ] *order_by_clause***)**  
 *partition_by_clause* divides the result set produced by the FROM clause into partitions to which the function is applied. If not specified, the function treats all rows of the query result set as a single group. *order_by_clause* determines the logical order in which the operation is performed. *order_by_clause* is required. For more information, see [OVER Clause (Transact-SQL)](../../t-sql/queries/select-over-clause-transact-sql.md).  
  
## Return Types  
 **float**  
  
## Remarks  
 If VAR is used on all items in a SELECT statement, each value in the result set is included in the calculation. VAR can be used with numeric columns only. Null values are ignored.  
  
 VAR is a deterministic function when used without the OVER and ORDER BY clauses. It is nondeterministic when specified with the OVER and ORDER BY clauses. For more information, see [Deterministic and Nondeterministic Functions](../../relational-databases/user-defined-functions/deterministic-and-nondeterministic-functions.md).  
  
## Examples  
  
### A: Using VAR  
 The following example returns the variance for all bonus values in the `SalesPerson` table in the [!INCLUDE[ssSampleDBnormal](../../includes/sssampledbnormal-md.md)] database.  
  
```  
SELECT VAR(Bonus)  
FROM Sales.SalesPerson;  
GO  
```  
  
## Examples: [!INCLUDE[ssSDWfull](../../includes/sssdwfull-md.md)] and [!INCLUDE[ssPDW](../../includes/sspdw-md.md)]  
  
### B: Using VAR  
 The following example returns the statistical variance of the sales quota values in the table `dbo.FactSalesQuota`. The first column contains the variance of all distinct values and the second column contains the variance of all values including any duplicates values.  
  
```  
-- Uses AdventureWorks  
  
SELECT VAR(DISTINCT SalesAmountQuota)AS Distinct_Values, VAR(SalesAmountQuota) AS All_Values  
FROM dbo.FactSalesQuota;  
```  
  
 [!INCLUDE[ssResult](../../includes/ssresult-md.md)]  
  
 `Distinct_Values   All_Values`  
  
 `----------------  ----------------`  
  
 `159180469909.18   158762853821.10`  
  
### C. Using VAR with OVER  
 The following example returns the statistical variance of the sales quota values for each quarter in a calendar year. Notice that the ORDER BY in the OVER clause orders the statistical variance and the ORDER BY of the SELECT statement orders the result set.  
  
```  
-- Uses AdventureWorks  
  
SELECT CalendarYear AS Year, CalendarQuarter AS Quarter, SalesAmountQuota AS SalesQuota,  
       VAR(SalesAmountQuota) OVER (ORDER BY CalendarYear, CalendarQuarter) AS Variance  
FROM dbo.FactSalesQuota  
WHERE EmployeeKey = 272 AND CalendarYear = 2002  
ORDER BY CalendarQuarter;  
```  
  
 [!INCLUDE[ssResult](../../includes/ssresult-md.md)]  
  
 `Year  Quarter  SalesQuota              Variance`  
  
 `----  -------  ----------------------  -------------------`  
  
 `2002  1         91000.0000             null`  
  
 `2002  2        140000.0000             1200500000.00`  
  
 `2002  3         70000.0000             1290333333.33`  
  
 `2002  4        154000.0000             1580250000.00`  
  
## See Also  
 [Aggregate Functions (Transact-SQL)](../../t-sql/functions/aggregate-functions-transact-sql.md)   
 [OVER Clause (Transact-SQL)](../../t-sql/queries/select-over-clause-transact-sql.md)