regr_r2
regr_r2 介绍
regr_r2(y, x) - 返回组中非空对的确定系数,其中 y 是因变量,x 是自变量。
Examples:
> SELECT regr_r2(y, x) FROM VALUES (1, 2), (2, 2), (2, 3), (2, 4) AS tab(y, x);
0.2727272727272727
> SELECT regr_r2(y, x) FROM VALUES (1, null) AS tab(y, x);
NULL
> SELECT regr_r2(y, x) FROM VALUES (null, 1) AS tab(y, x);
NULL
> SELECT regr_r2(y, x) FROM VALUES (1, 2), (2, null), (2, 3), (2, 4) AS tab(y, x);
0.7500000000000001
> SELECT regr_r2(y, x) FROM VALUES (1, 2), (2, null), (null, 3), (2, 4) AS tab(y, x);
1.0
Since: 3.3.0