LOG10 (Transact-SQL)

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

Returns the base-10 logarithm of the specified float expression.

👁 Image
Transact-SQL syntax conventions

Syntax

LOG10 ( float_expression ) 

Arguments

float_expression
Is an expression of type float or of a type that can be implicitly converted to float.

Return Types

float

Remarks

The LOG10 and POWER functions are inversely related to one another. For example, 10 ^ LOG10(n) = n.

Examples

A. Calculating the base 10 logarithm for a variable.

The following example calculates the LOG10 of the specified variable.

DECLARE @var FLOAT; 
SET @var = 145.175643; 
SELECT 'The LOG10 of the variable is: ' + CONVERT(VARCHAR,LOG10(@var)); 
GO 

Here's the result set.

The LOG10 of the variable is: 2.16189 
 
(1 row(s) affected) 

B. Calculating the result of raising a base-10 logarithm to a specified power.

The following example returns the result of raising a base-10 logarithm to a specified power.

SELECT POWER (10, LOG10(5)); 

Here's the result set.

----------- 
5 
 
(1 row(s) affected) 

Examples: Azure Synapse Analytics and Analytics Platform System (PDW)

C: Calculating the base 10 logarithm for a value.

The following example calculates the LOG10 of the specified value.

SELECT LOG10(145.175642); 

Here's the result set.

------------------- 
2.16

See Also

Mathematical Functions (Transact-SQL)
POWER (Transact-SQL)
LOG (Transact-SQL)