/*

148.VAR

Aggregate function:

VAR( [ ALL | DISTINCT ] <expression> )

Window function:

VAR( <expression> ) <window_specification>

Returns the variance of the given expression as the square of the standard deviation.

方差

VAR_POP(<expression>)

Returns the population variance of an expression.

VAR_SAMP(<expression>)

Returns the sample variance of an expression.

*/

SELECT VAR("Price") FROM "MyProducts";
SELECT VAR_POP("Price") FROM "MyProducts";
SELECT VAR_SAMP("Price") FROM "MyProducts";