CUME_DIST

说明

计算每一行排名的相对位置，用百分比表示。

语法

cume_dist ::=

参数

query_partition_clause

一个分区语句。

order_by_clause

一个排序语句。

返回值

计算出的百分比值。

注解

函数返回类型和参数类型均为数字类型，返回值的范围是(0,1]

示例

示例1: 计算排名的比例

--  清理环境
DROP TABLE tab1 CASCADE;

--  创建表并插入数据
create table tab1(id INT, a INT, b INT);

INSERT INTO tab1 VALUES(1, 21, 55);
INSERT INTO tab1 VALUES(2, 21, 56);
INSERT INTO tab1 VALUES(3, 21, 48);
INSERT INTO tab1 VALUES(4, 22, 70);
INSERT INTO tab1 VALUES(5, 22, 65);
INSERT INTO tab1 VALUES(6, 11, 40);
INSERT INTO tab1 VALUES(7, 11, 43);
INSERT INTO tab1 VALUES(8, 31, 77);
INSERT INTO tab1 VALUES(9, 32, 80);


SELECT * FROM tab1 ORDER BY id;
ID(int)      |A(int)      |B(int)      |
-------------------------------------
1            |21          |55          |
-------------------------------------
2            |21          |56          |
-------------------------------------
3            |21          |48          |
-------------------------------------
4            |22          |70          |
-------------------------------------
5            |22          |65          |
-------------------------------------
6            |11          |40          |
-------------------------------------
7            |11          |43          |
-------------------------------------
8            |31          |77          |
-------------------------------------
9            |32          |80          |
总数目：9


--  计算排名的比例
SELECT id, a, b, CUME_DIST() OVER (PARTITION BY a ORDER BY a) FROM tab1 ORDER BY id;
ID(int)      |A(int)      |B(int)      |CUME_DIST(double precision)      |
----------------------------------------------------------------------
1            |21          |55          |1                                |
----------------------------------------------------------------------
2            |21          |56          |1                                |
----------------------------------------------------------------------
3            |21          |48          |1                                |
----------------------------------------------------------------------
4            |22          |70          |1                                |
----------------------------------------------------------------------
5            |22          |65          |1                                |
----------------------------------------------------------------------
6            |11          |40          |1                                |
----------------------------------------------------------------------
7            |11          |43          |1                                |
----------------------------------------------------------------------
8            |31          |77          |1                                |
----------------------------------------------------------------------
9            |32          |80          |1                                |
总数目：9

--  删除表
DROP TABLE tab1;