covar_samp
covar_samp介绍
covar_samp(expr1, expr2) - 返回一组数字对的样本协方差。
Examples:
> SELECT covar_samp(c1, c2) FROM VALUES (1,1), (2,2), (3,3) AS tab(c1, c2);
1.0
Since: 2.0.0
covar_samp(expr1, expr2) - 返回一组数字对的样本协方差。
Examples:
> SELECT covar_samp(c1, c2) FROM VALUES (1,1), (2,2), (3,3) AS tab(c1, c2);
1.0
Since: 2.0.0