VARIANCE/VAR_SAMP

Applies to: ✅ Data 360 SQL ✅ Tableau Hyper API

Computes the sample variance of input values.

1variance(<expression>)

• <expression>: An expression of any numerical type.

• NUMERIC(38,6) for integer-type or numeric arguments.
• double precision for floating-point arguments.

Returns NULL if the computation is meaningless.

• Uses N-1 in the denominator (Bessel’s correction).
• Variance is the square of the standard deviation.
• Use VAR_POP for population variance.
• Cast the input to double precision to get a double precision result.

Find the variance of prices.

1SELECT variance(price) AS price_variance
2FROM products;

Calculate variance for each category.

1SELECT category, variance(price) AS price_variance
2FROM products
3GROUP BY category;

• VAR_POP
• COVAR_SAMP/VAR_SAMP
• STDDEV
• Aggregate Functions