SQL Oracle查询,用于比较公司每项工作的男性与女性工资

Question

使用以下列为每个Job_ID返回一行:

•J ob ID

• 该职位的平均女性服务年限为四年至十年

• 该工作的平均女性工资

• 该职位的平均男性服务年限为四年,一年到十分之一

• 该工作的平均男性工资

• 该工作的男女平均工资差异,正数表示女性平均工资较高,负数表示男性工资平均较高.

表

HR.EMPLOYEES

Name           Null     Type         
-------------- -------- ------------ 
EMPLOYEE_ID    NOT NULL NUMBER(6)    
FIRST_NAME              VARCHAR2(20) 
LAST_NAME      NOT NULL VARCHAR2(25) 
EMAIL          NOT NULL VARCHAR2(25) 
PHONE_NUMBER            VARCHAR2(20) 
HIRE_DATE      NOT NULL DATE         
JOB_ID         NOT NULL VARCHAR2(10) 
SALARY                  NUMBER(8,2)  
COMMISSION_PCT          NUMBER(2,2)  
MANAGER_ID              NUMBER(6)    
DEPARTMENT_ID           NUMBER(4)    
GENDER                  CHAR(1) 

我到目前为止, 但这是为每个job_id返回一个M&F行我需要M&F列

SELECT gender, job_id, ROUND(AVG(salary),0) as avg_job_salary,
(SELECT ROUND(AVG(salary),0)
FROM hr.employees 
WHERE gender = 'M') AS avg_m_salary, (SELECT ROUND(AVG(salary),0) 
FROM hr.employees 
WHERE gender = 'F') AS avg_f_salary,
ROUND(AVG(days_of_svc/365),1) AS avg_years_svc
FROM (SELECT  job_id, salary, gender, (SYSDATE-hire_date) AS  days_of_svc 
FROM hr.employees)
GROUP BY job_id,gender
ORDER BY job_id, gender;

或版本2

SELECT gender, job_id, ROUND(AVG(salary),0) as avg_job_salary, 
((SELECT ROUND(AVG(salary),0)
FROM hr.employees 
WHERE gender = 'F') - (SELECT ROUND(AVG(salary),0) 
FROM hr.employees 
WHERE gender = 'M')) as diff,
ROUND(AVG(days_of_svc/365),1) AS avg_years_svc
FROM (SELECT  job_id, salary, gender, (SYSDATE-hire_date) AS  days_of_svc 
FROM hr.employees)
GROUP BY job_id,gender
ORDER BY job_id, gender;

样本预期结果行

JOB_ID    F_AVG_LENGTH F_AVG_SAL M_AVG_LENGTH M_AVG_SAL DIFFERENCE
------    ------------ --------- ------------ --------- ----------
MAILCLERK         24.1     48000         23.4     47000       1000
CASHIER            4.6     12000          4.4     13500      -1500

Answer 1

在我的机器上，我在架构中制作了一个副本HR.EMPLOYEES，并将其命名为克隆HR_EMPLOYEES。然后我添加了一列，GENDER因为在我的 Oracle 副本上，该HR.EMPLOYEES表没有GENDER列。我在该专栏中填充了我的最佳猜测，仅供测试之用。

在Oracle 11中，您可以使用PIVOT操作，这使工作变得更容易。我将平均任期除以 365.25，因此它以年而不是天来表示。请注意，有许多工作要么没有男性，要么没有女性，因此有很多 NULL 结果。我假设你也希望它们显示 - 否则它们可以被排除在外。

select job_id, round(F_AVG_TENURE_D/365.25, 1)    as f_avg_length, 
               round(F_AVG_SALARY)                as f_avg_salary,
               round(M_AVG_TENURE_D/365.25, 1)    as m_avg_length, 
               round(M_AVG_SALARY)                as m_avg_salary,       
               round(F_AVG_SALARY - M_AVG_SALARY) as avg_sal_diff
from  ( 
        select job_id, gender, sysdate - hire_date as tenure, salary
        from   hr_employees
      )
pivot (avg(tenure) as avg_tenure_d, avg(salary) as avg_salary 
                                                for gender in ('F' as F, 'M' as M))
order by avg_sal_diff desc nulls last, job_id   --  ORDER BY is optional
;

输出：

JOB_ID     F_AVG_LENGTH F_AVG_SALARY M_AVG_LENGTH M_AVG_SALARY AVG_SAL_DIFF
---------- ------------ ------------ ------------ ------------ ------------
SH_CLERK           11.2         3511          9.9         2973          538
ST_MAN             12.3         7467         10.3         7000          467
ST_CLERK           10.5         2883         10.8         2743          140
PU_CLERK           11.6         2833           10         2700          133
AD_VP              11.1        17000         15.8        17000            0
SA_REP             10.3         8244         10.6         8471         -228
SA_MAN             10.3        12000         10.9        12333         -333
IT_PROG            10.2         4500         10.5         6600        -2100
AC_ACCOUNT                                   14.4         8300
AC_MGR             14.4        12008
AD_ASST            13.1         4400
AD_PRES                                      13.4        24000
FI_ACCOUNT                                   11.2         7920
FI_MGR             14.2        12008
HR_REP             14.4         6500
MK_MAN                                       12.7        13000
MK_REP             11.2         6000
PR_REP                                       14.4        10000
PU_MAN                                       13.9        11000

19 rows selected.