Comparing LOG and LOG10
The LOG function returns the natural logarithm for the specified float expression. Natural logarithms are calculated by using the base-e system. However, the LOG10 function returns the base-10 logarithm. Use LOG and LOG10 for statistics and data analysis. The following SELECT statement calculates the logarithm of the value 1.75 in base-e, base-10, and base-2.
SELECT LOG(1.75) AS 'base-e'
,LOG10(1.75) AS 'base-10'
,LOG(1.75)/LOG(2) AS 'base-2';
GO
Here is the result set.
base-e base-10 base-2
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0.559615787935423 0.243038048686294 0.807354922057604