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slug | sidebar_position |
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/en/sql-reference/aggregate-functions/reference/stddevsamp | 190 |
stddevSamp
The result is equal to the square root of varSamp.
Alias: STDDEV_SAMP
.
:::note
This function uses a numerically unstable algorithm. If you need numerical stability in calculations, use the stddevSampStable
function. It works slower but provides a lower computational error.
:::
Syntax
stddevSamp(x)
Parameters
Returned value
Square root of sample variance of x
. Float64.
Example
Query:
DROP TABLE IF EXISTS test_data;
CREATE TABLE test_data
(
population UInt8,
)
ENGINE = Log;
INSERT INTO test_data VALUES (3),(3),(3),(4),(4),(5),(5),(7),(11),(15);
SELECT
stddevSamp(population)
FROM test_data;
Result:
┌─stddevSamp(population)─┐
│ 4 │
└────────────────────────┘