計算排名。輸出百分比格式。
使用限制
視窗函數的使用限制如下:
視窗函數只能出現在
select
語句中。視窗函數中不能嵌套使用視窗函數和彙總函式。
視窗函數不能和同層級的彙總函式一起使用。
命令格式
double percent_rank() over([partition_clause] [orderby_clause])
命令說明
計算當前行在分區中按照orderby_clause排序後的百分比排名。
參數說明
partition_clause及orderby_clause:詳情請參見windowing_definition。
傳回值說明
返回DOUBLE類型,範圍為[0.0, 1.0]。具體的傳回值等於“(rank - 1) / (partition_row_count - 1)”
,其中:rank
為該行資料的RANK視窗函數的返回結果,partition_row_count
為該行資料所屬分區的資料行數。當分區中只有一行資料時,輸出結果為0.0。
樣本資料
為便於理解各函數的使用方法,本文為您提供來源資料,基於來源資料提供函數相關樣本。建立表emp,並添加資料,命令樣本如下:
create table if not exists emp
(empno bigint,
ename string,
job string,
mgr bigint,
hiredate datetime,
sal bigint,
comm bigint,
deptno bigint);
tunnel upload emp.txt emp; --請根據您上傳資料檔案的實際path(路徑以及名稱)替換emp.txt
emp.txt中的資料如下:
7369,SMITH,CLERK,7902,1980-12-17 00:00:00,800,,20
7499,ALLEN,SALESMAN,7698,1981-02-20 00:00:00,1600,300,30
7521,WARD,SALESMAN,7698,1981-02-22 00:00:00,1250,500,30
7566,JONES,MANAGER,7839,1981-04-02 00:00:00,2975,,20
7654,MARTIN,SALESMAN,7698,1981-09-28 00:00:00,1250,1400,30
7698,BLAKE,MANAGER,7839,1981-05-01 00:00:00,2850,,30
7782,CLARK,MANAGER,7839,1981-06-09 00:00:00,2450,,10
7788,SCOTT,ANALYST,7566,1987-04-19 00:00:00,3000,,20
7839,KING,PRESIDENT,,1981-11-17 00:00:00,5000,,10
7844,TURNER,SALESMAN,7698,1981-09-08 00:00:00,1500,0,30
7876,ADAMS,CLERK,7788,1987-05-23 00:00:00,1100,,20
7900,JAMES,CLERK,7698,1981-12-03 00:00:00,950,,30
7902,FORD,ANALYST,7566,1981-12-03 00:00:00,3000,,20
7934,MILLER,CLERK,7782,1982-01-23 00:00:00,1300,,10
7948,JACCKA,CLERK,7782,1981-04-12 00:00:00,5000,,10
7956,WELAN,CLERK,7649,1982-07-20 00:00:00,2450,,10
7956,TEBAGE,CLERK,7748,1982-12-30 00:00:00,1300,,10
樣本
計算員工薪水在組內的百分比排名。命令樣本如下:
select deptno, ename, sal, percent_rank() over (partition by deptno order by sal desc) as sal_new from emp;
返回結果如下:
+------------+------------+------------+------------+
| deptno | ename | sal | sal_new |
+------------+------------+------------+------------+
| 10 | JACCKA | 5000 | 0.0 |
| 10 | KING | 5000 | 0.0 |
| 10 | CLARK | 2450 | 0.4 |
| 10 | WELAN | 2450 | 0.4 |
| 10 | TEBAGE | 1300 | 0.8 |
| 10 | MILLER | 1300 | 0.8 |
| 20 | SCOTT | 3000 | 0.0 |
| 20 | FORD | 3000 | 0.0 |
| 20 | JONES | 2975 | 0.5 |
| 20 | ADAMS | 1100 | 0.75 |
| 20 | SMITH | 800 | 1.0 |
| 30 | BLAKE | 2850 | 0.0 |
| 30 | ALLEN | 1600 | 0.2 |
| 30 | TURNER | 1500 | 0.4 |
| 30 | MARTIN | 1250 | 0.6 |
| 30 | WARD | 1250 | 0.6 |
| 30 | JAMES | 950 | 1.0 |
+------------+------------+------------+------------+
相關函數
PERCENT_RANK函數屬於視窗函數,更多對指定開窗列的資料進行求和、數值排序的相關函數請參見視窗函數。