STDDEV_POP
Aggregate function.
The STDDEV_POP() function returns the population standard deviation(the square root of VAR_POP()) of an expression.
tip
STD() or STDDEV() can also be used, which are equivalent but not standard SQL.
caution
NULL values are not counted.
Syntax
STDDEV_POP(<expr>)
STDDEV(<expr>)
STD(<expr>)
Arguments
Arguments | Description |
---|---|
<expr> | Any numerical expression |
Return Type
double
Example
Create a Table and Insert Sample Data
CREATE TABLE test_scores (
id INT,
student_id INT,
score FLOAT
);
INSERT INTO test_scores (id, student_id, score)
VALUES (1, 1, 80),
(2, 2, 85),
(3, 3, 90),
(4, 4, 95),
(5, 5, 100);
Query Demo: Calculate Population Standard Deviation of Test Scores
SELECT STDDEV_POP(score) AS test_score_stddev_pop
FROM test_scores;
Result
| test_score_stddev_pop |
|-----------------------|
| 7.07107 |