How the LOG10() function works in Mariadb?

The LOG10() function is a mathematical function that returns the logarithm of a number to the base 10.

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The LOG10() function is a mathematical function that returns the logarithm of a number to the base 10. The logarithm to the base 10 is also known as the common logarithm, as it is widely used in mathematics and science. The LOG10() function is useful for performing various calculations, such as order of magnitude, scientific notation, pH, etc.

Syntax

The syntax of the LOG10() function is as follows:

LOG10(number)

The number argument is the number whose logarithm to the base 10 is to be returned. The number argument must be a positive value, otherwise the function returns NULL.

The LOG10() function returns a decimal value that represents the logarithm of the number to the base 10. If the number argument is NULL, the function returns NULL.

Examples

Example 1: Basic usage of the LOG10() function

The following example shows how to use the LOG10() function with a simple number. It returns the logarithm of the number 100 to the base 10.

SELECT LOG10(100);

The output is:

2

This means that the logarithm of 100 to the base 10 is 2, which means that 100 is 10 raised to the power of 2.

Example 2: Using the LOG10() function with a decimal number

The following example shows how to use the LOG10() function with a decimal number. It returns the logarithm of the number 0.01 to the base 10.

SELECT LOG10(0.01);

The output is:

-2

This means that the logarithm of 0.01 to the base 10 is -2, which means that 0.01 is 10 raised to the power of -2.

Example 3: Using the LOG10() function with a negative number

The following example shows what happens when the LOG10() function is used with a negative number. It returns NULL, indicating that the logarithm to the base 10 is not defined for negative numbers.

SELECT LOG10(-5);

The output is:

NULL

This means that the logarithm of -5 to the base 10 is not defined.

There are some other functions that are related to the LOG10() function in Mariadb. They are:

  • LOG(): This function returns the natural logarithm of a number. The natural logarithm is the logarithm to the base e, where e is the mathematical constant that is approximately equal to 2.71828. The LOG() function can also accept an optional second argument that specifies a different base for the logarithm.
  • LOG2(): This function returns the logarithm of a number to the base 2. The logarithm to the base 2 is also known as the binary logarithm, as it represents the number of times a number can be divided by 2.
  • POW(): This function returns the value of a number raised to the power of another number. It is the inverse of the LOG() function, meaning that POW(10, LOG10(x)) = x for any positive x.

Here are some examples of using these related functions:

-- Get the natural logarithm of 10
SELECT LOG(10);

-- Get the logarithm of 16 to the base 2
SELECT LOG2(16);

-- Get the value of 10 raised to the power of 3
SELECT POW(10, 3);

Conclusion

In this article, we have learned how the LOG10() function works in Mariadb. We have seen its syntax, examples, and related functions. We have also learned how to use the LOG10() function to calculate the logarithm of a number to the base 10. The LOG10() function is a useful function to perform various calculations, such as order of magnitude, scientific notation, pH, etc.