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ABS (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric

A mathematical function that returns the absolute (positive) value of the specified numeric expression. (ABS changes negative values to positive values. ABS has no effect on zero or positive values.)

Transact-SQL syntax conventions

Syntax

ABS ( numeric_expression )  

Arguments

numeric_expression
An expression of the exact numeric or approximate numeric data type category.

Return types

The return type depends on the input type of numeric_expression:

Input type Return type
float, real float
decimal(p, s) decimal(38, s)
int, smallint, tinyint int
bigint bigint
money, smallmoney money
bit float

If the result does not fit in the return type, an arithmetic overflow error occurs.

Examples

This example shows the results of using the ABS function on three different numbers.

SELECT ABS(-1.0), ABS(0.0), ABS(1.0);  

Here's the result set.

---- ---- ----  
1.0  .0   1.0  

The ABS function can produce an overflow error when the absolute value of a number exceeds the largest number that the specified data type can represent. For example, the int data type has a value range from -2,147,483,648 to 2,147,483,647. Computing the absolute value for the signed integer -2,147,483,648 will cause an overflow error because its absolute value exceeds the positive range limit for the int data type.

DECLARE @i INT;  
SET @i = -2147483648;  
SELECT ABS(@i);  
GO  

Returns this error message:

"Msg 8115, Level 16, State 2, Line 3"

"Arithmetic overflow error converting expression to data type int."

See also

CAST and CONVERT (Transact-SQL)
Data Types (Transact-SQL)
Mathematical Functions (Transact-SQL)
Built-in Functions (Transact-SQL)