STD
Aggregate function. Calculates the population standard deviation value from a set of numbers. STD has synonyms STDDEV and STDDEV_POP which are equivalent.
Syntax
STD returns NULL if there are not matching rows.
STD ( expression )
Arguments
expression: any expression. This may be a column name, the result of another function, or a math operation.
Return Type
A double.
Examples
SELECT STD(table_rows) FROM information_schema.tables; +-----------------+ | STD(table_rows) | +-----------------+ | 2.1500 | +-----------------+ 1 row in set (2.87 sec)