STDDEV_SAMP

description

Syntax

STDDEV_SAMP(expr)

It returns the sample standard deviation of the expr expression

example

MySQL > select stddev_samp(scan_rows)
from log_statis
group by datetime;
+--------------------------+
| stddev_samp(`scan_rows`) |
+--------------------------+
|        2.372044195280762 |
+--------------------------+

keyword

STDDEV_SAMP,STDDEV,SAMP