Question

是否有任何oracle函数可以帮助我计算接受某些条件的行的百分比

示例表：

   WorkerId   Salary    DepartmentId

   10001       2000.00      1
   10002       2500.00      2
   10004       3000.00      1
   10005       3500.00      1

我想知道每个部门工资超过2100.00的工人百分比

Answer 1

您可以使用RATIO_TO_REPORT：

SELECT departmentID, 100 * SUM(rr) AS total_percentage
FROM  (SELECT t.*, RATIO_TO_REPORT(1) OVER (PARTITION BY DepartmentId) AS rr
       FROM your_tab t) s
WHERE salary > 2100
GROUP BY departmentId;

<强> DBFiddle Demo

输出：

DEPARTMENTID TOTAL_PERCENTAGE
1            66.66
2            100

Answer 2

尝试使用两个GROUP BY和JOIN

SELECT yt.DepartmentId, t.hs/count(*) * 100
FROM your_tab yt
JOIN 
(
   SELECT DepartmentId, count(*) as hs
   FROM your_tab
   WHERE salary > 2100
   GROUP BY DepartmentId
) t ON yt.DepartmentId = t.DepartmentId
GROUP BY yt.DepartmentId, t.hs

dbfiddle

Answer 3

您无需使用分析函数即可完成此操作，如下所示：

WITH sample_data AS (SELECT 10001 workerid, 2000 salary, 1 departmentid FROM dual UNION ALL
                     SELECT 10002 workerid, 2500 salary, 2 departmentid FROM dual UNION ALL
                     SELECT 10004 workerid, 3000 salary, 1 departmentid FROM dual UNION ALL
                     SELECT 10005 workerid, 3500 salary, 1 departmentid FROM dual)
-- end of subquery mimicking a table with your data in it.
-- see SQL query below:
SELECT departmentid,
       100*(COUNT(CASE WHEN salary > 2100 THEN 1 END)/COUNT(*)) pct_earning_gt_2100
FROM   sample_data
GROUP BY departmentid;

DEPARTMENTID PCT_EARNING_GT_2100
------------ -------------------
           1    66.6666666666667
           2                 100

这使用条件计数（请记住，大多数聚合函数都会忽略空值）来确定在除以每个部门的总行数之前满足条件的行数。

这应该比涉及ratio_to_report分析函数的解决方案更高效，因为在执行group by之前不需要执行额外的步骤，但是您应该测试两个解决方案以找出哪个实际上更好数据

计算某个特定值的百分比行数

3 个答案: