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MySQL LOG2() Function

The MySQL LOG2() function returns the base-2 logarithm of a given number. In special cases it returns the following:

  • If the number is less than or equal to 0, then NULL is returned.




number Required. Specify the number. Must be greater than 0.

Return Value

Returns the base-2 logarithm of a given number.

Example 1:

The example below shows the usage of LOG2() function.

mysql> SELECT LOG2(1);
Result: 0

mysql> SELECT LOG2(1.5);
Result: 0.5849625007211562

mysql> SELECT LOG2(2);
Result: 1

mysql> SELECT LOG2(5);
Result: 2.321928094887362

mysql> SELECT LOG2(10);
Result: 3.3219280948873626

mysql> SELECT LOG2(0);
Result: NULL

Example 2:

Consider a database table called Sample with the following records:

Data 10.5
Data 21
Data 35
Data 410
Data 550

The query given below can be used to calculate the base-2 logarithm of column x.

SELECT *, LOG2(x) AS LOG2_Value FROM Sample;

This will produce the result as shown below:

Data 10.5-1
Data 210
Data 352.321928094887362
Data 4103.3219280948873626
Data 5505.643856189774724

❮ MySQL Functions