LOG2

log2(expr)

Function Description

The LOG2 function is used to calculate the base-2 logarithm of a given value expr. This function has wide applications in computer science, information theory, and other fields, such as calculating the number of bits in a binary number or evaluating information entropy.

Parameter Description

• expr (double type): The value for which the logarithm needs to be calculated.

Return Result

Returns the base-2 logarithm of expr, with the result being of double type.

Example

1. Calculate the base-2 logarithm of 2:

SELECT log2(2); -- Result is 1.0

2. Calculate the base-2 logarithm of 8:

SELECT log2(8); -- Result is 3.0

3. Calculate the base-2 logarithm of 1024:

SELECT log2(1024); -- Result is 10.0

Notes

• When expr is a negative number or non-numeric, the LOG2 function will return NULL.