SQL Reference

LOG

LOG is a mathematical function in SQL that returns the logarithm of a specified number to a specified base. The base is user-defined. The LOG function is primarily used for mathematical computations in mathematical modeling, predictions, and calculations. It is part of the category of Mathematical Numeric Functions in SQL.

LOG(X)LOG(B, X)

b: The base of the logarithm. It is a positive number that is not equal to 1. If B is not specified, the base defaults to 10.
x: The number for which the logarithm is to be calculated. It is a positive number. If X is equal to 1, the result is 0; If X is less than 1, the result is negative.

Example

SELECT LOG(10);

Output

2.30258509299404568402

Explanation

The LOG() function in MySQL performs a natural logarithm of a number. In the above example, it calculates the natural logarithm of 10, resulting in an output of approximately 2.3026.

LOG(float_expression [, base])

float_expression: Represents a float expression which is a number or a name of a column that includes float data to calculate the logarithmic value of.
base: An optional parameter. This float expression will determine the base for the logarithmic calculation. If provided, it calculates a logarithm with the specified base. If not, it defaults to base 10.

Example

SELECT LOG(10);

Output

2.30258509299405

Explanation

The LOG function returns the natural logarithm of the provided positive number. In the above example, we’ve calculated the natural logarithm of 10, which results in 2.30258509299405.

LOG(n, value)

n: This parameter specifies the base of the logarithm operation. Choosing a specific number for ‘n’ will perform the log calculation based on that base number.
value: This parameter signifies the number for which the logarithm operation will be performed. The function will return the logarithm of this ‘value’ with respect to the base ‘n’.

Example

SELECT LOG(10, 100) FROM dual;

Output

Explanation

The LOG function in Oracle is used to calculate the logarithm of a number. In the provided example, we calculate the logarithm of 100 with the base 10. The result is 2, which means that 10 raised to the power of 2 is equal to 100.