VARIANCE

1
SELECT
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  VARIANCE(price) as variance_price,
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  STDDEV(price) as stddev_price,
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  SQRT(VARIANCE(price)) as stddev_from_variance
5
FROM products;

1
SELECT
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  department,
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  COUNT(*) as employee_count,
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  ROUND(VARIANCE(salary), 2) as salary_variance
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FROM employees
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GROUP BY department
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ORDER BY salary_variance DESC;

1
SELECT
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  VAR_SAMP(revenue) as sample_variance,
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  VAR_POP(revenue) as population_variance
4
FROM monthly_sales;