log

log

description

Syntax

DOUBLE log(DOUBLE b, DOUBLE x) 返回基于底数b的x的对数.

example

mysql> select log(5,1);
+---------------+
| log(5.0, 1.0) |
+---------------+
|             0 |
+---------------+
mysql> select log(3,20);
+--------------------+
| log(3.0, 20.0)     |
+--------------------+
| 2.7268330278608417 |
+--------------------+
mysql> select log(2,65536);
+-------------------+
| log(2.0, 65536.0) |
+-------------------+
|                16 |
+-------------------+

keywords

LOG