VARIANCE
Aggregate function. Calculates the population variance value from a set of numbers. VARIANCE has synonym VAR_POP which is equivalent. VARIANCE returns NULL if there are not matching rows.
Syntax
VARIANCE ( 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 VARIANCE(table_rows) FROM information_schema.tables; +----------------------+ | VARIANCE(table_rows) | +----------------------+ | 2.1500 | +----------------------+ 1 row in set (2.87 sec)