STDDEV_POP() GROUP BY ...

All functions > GROUP BY > STDDEV_POP() GROUP BY ...

Returns the population standard deviation of the values in the group.

Syntax

STDDEV_POP(expr)
 [ FILTER (WHERE condition) ]
  [ GROUP BY feature [, feature ...] ]

STDDEV_POP(expr)
 [ FILTER (WHERE condition) ]
  [ GROUP BY feature [, feature ...] ]

Notes

• Computes the population standard deviation (divides by N)
• NULL values are excluded from the calculation
• Returns NULL if all values are NULL or group is empty

Examples

SELECT
    f1 := ZIP(ARRAY[1, 2, 3, 4] AS value).TRANSFORM(SELECT STDDEV_POP(value)).UNWRAP_ONE() -- Population standard deviation
;