MySQL LOG10() Function

 The LOG10() function in MySQL is used to calculate the base-10 logarithm of a given numeric value. It is commonly used in mathematical computations where base-10 logarithmic operations are required.

Syntax

LOG10(number)

Parameters

• number: The numeric value for which the base-10 logarithm is to be calculated. It must be greater than 0, as logarithms are undefined for non-positive values.

Returns

• The base-10 logarithm of the input number.
• Returns NULL if the input number is NULL.
• If the input number is less than or equal to 0, it generates an error or returns NULL.

Examples

1. Basic Usage

SELECT LOG10(100) AS Logarithm;

Output: 2
Explanation: $\log_{10}(100) = 2$

2. Using Decimal Values

SELECT LOG10(1000.5) AS Logarithm;

Output: 3.000217 (approximately)
Explanation: $\log_{10}(1000.5)$

3. Handling Negative Numbers

SELECT LOG10(-10) AS Logarithm;

Output: NULL
Explanation: Logarithms of negative numbers are undefined in real numbers.

4. Working with Zero

SELECT LOG10(0) AS Logarithm;

Output: NULL
Explanation: Logarithms are undefined for zero.

5. Using NULL

SELECT LOG10(NULL) AS Logarithm;

Output: NULL
Explanation: The input is NULL, so the result is also NULL.

6. Using LOG10 in a Calculation

SELECT LOG10(100) * 2 AS Result;

Output: 4
Explanation: $\log_{10}(100) \times 2 = 4$

Notes

• Ensure the input value is greater than zero to avoid errors.
• For natural logarithms, use the LOG() function (which defaults to base $e$).

Would you like help with practical use cases or additional details?