MySQL LN() Function

The LN() function in MySQL is used to return the natural logarithm (logarithm to the base e) of a number.

Syntax

LN(number)

Definition and Usage

• The LN() function computes the natural logarithm of the given number.
• The natural logarithm is the logarithm to the base e, where e is approximately 2.71828.
• The argument must be greater than 0. If the argument is less than or equal to 0, it returns NULL.

Parameter Values

Technical Details

• Works in: From MySQL 4.0
• Return Value: The natural logarithm of the number (a floating-point value).

Examples

Example 1: Return the natural logarithm of 2

SELECT LN(2);

Result:

LN(2): 0.693147

Explanation: The natural logarithm of 2 is approximately 0.693147.

Example 2: Return the natural logarithm of 1

SELECT LN(1);

Result:

LN(1): 0

Explanation: The natural logarithm of 1 is always 0, as e^0 = 1.

Example 3: Return the natural logarithm of a number greater than 1

SELECT LN(10);

Result:

LN(10): 2.302585

Explanation: The natural logarithm of 10 is approximately 2.302585.

Related Functions

• LOG(): Computes the logarithm of a number to a specified base. If no base is provided, it defaults to the natural logarithm (same as LN()).
• EXP(): Computes e raised to the power of the given number.

Usage Notes

• The LN() function is most commonly used in calculations involving growth, decay, and continuous compounding, as the natural logarithm is frequently used in calculus and mathematics.
• The argument must always be greater than 0, as logarithms of non-positive numbers are undefined in real numbers.