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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(expression)
STDDEV(expression)
STD(expression)

Arguments​

ArgumentsDescription
expressionAny numerical expression

Return Type​

double

Examples​

tip

numbers(N) – A table for test with the single number column (UInt64) that contains integers from 0 to N-1.

mysql> SELECT STDDEV_POP(number) FROM numbers(10000);
+--------------------+
| STDDEV_POP(number) |
+--------------------+
|  2886.751331514372 |
+--------------------+

mysql> SELECT STDDEV(number) FROM numbers(1000);
+--------------------+
| STDDEV(number)     |
+--------------------+
| 288.67499025720946 |
+--------------------+

mysql> SELECT STD(number) FROM numbers(100);
+-------------------+
| STD(number)       |
+-------------------+
| 28.86607004772212 |
+-------------------+