PERCENTILE_APPROX_WEIGHTED

PERCENTILE_APPROX_WEIGHTED

description

Syntax

PERCENTILE_APPROX_WEIGHTED(expr, w ,DOUBLE p [, DOUBLE compression])

该函数和PERCENTILE_APPROX类似，唯一的区别是多了一个参数w，用来表示expr出现的次数。

example

mysql >select * from quantile_weighted_table order by k;
+------+------+
| k    | w    |
+------+------+
|    1 |    2 |
|    3 |    1 |
|    5 |    2 |
+------+------+


mysql >select percentile_approx_weighted(k,w,0.55) from quantile_weighted_table;
+----------------------------------------------------------------------------------------+
| percentile_approx_weighted(cast(k as DOUBLE), cast(w as DOUBLE), cast(0.55 as DOUBLE)) |
+----------------------------------------------------------------------------------------+
|                                                                     3.3333332538604736 |
+----------------------------------------------------------------------------------------+

keywords

PERCENTILE_APPROX,PERCENTILE,APPROX,PERCENTILE_APPROX_WEIGHTED