📣
TiDB Cloud Premium is now in public preview. Unlimited growth, instant elasticity, advanced security for enterprise workloads. Try it out →

STDDEV_SAMP



Returns the sample standard deviation (the square root of VAR_SAMP()) of an expression.

  • NULL values are ignored.
  • STDDEV_SAMP() returns NULL instead of 0 when there is only one input record.

Syntax

STDDEV_SAMP(<expr>)

Arguments

ArgumentsDescription
<expr>Any numerical expression

Return Type

Double.

Example

Create a Table and Insert Sample Data

CREATE TABLE height_data ( id INT, person_id INT, height FLOAT ); INSERT INTO height_data (id, person_id, height) VALUES (1, 1, 5.8), (2, 2, 6.1), (3, 3, 5.9), (4, 4, 5.7), (5, 5, 6.3);

Query Demo: Calculate Sample Standard Deviation of Heights

SELECT STDDEV_SAMP(height) AS height_stddev_samp FROM height_data;

Result

| height_stddev_samp | |--------------------| | 0.240 |

Was this page helpful?