stddev()

Calculate the standard deviation from a one-dimensional statistical aggregate

Since 1.3.0

Calculate the standard deviation from the values in a statistical aggregate.

Samples

Calculate the standard deviation of a sample containing the integers from 0 to 100:

SELECT stddev(stats_agg(data))
  FROM generate_series(0, 100) data;

stddev_y
--------
29.3002

The syntax is:

stddev(
  summary StatsSummary1D,
  [ method TEXT ]
) RETURNS DOUBLE PRECISION

Name	Type	Default	Required	Description
summary	StatsSummary1D	-	✔	The statistical aggregate produced by a `stats_agg` call
method	TEXT	`sample`	-	The method used for calculating the standard deviation. The two options are `population` and `sample`, which can be abbreviated to `pop` or `samp`

Column	Type	Description
stddev	DOUBLE PRECISION	The standard deviation of the values in the statistical aggregate