STDDEV_SAMP
Description
Syntax
STDDEV SAMP (expr)
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 |
+--------------------------+keywords
STDDEV SAMP,STDDEV,SAMP