如何在MySql中执行求和、减法和除法

我有一个以下问题，它给了我一个开场白/消耗/移动/添加：

select(select SUM(Opening_HC) from(
(select count(emp_id) as Opening_HC from hcdata where status = 

"Active" and DOJ <='2014-11-02' and sub_department='Sub_dep_07' and 

production_support='prod_sup-02')
UNION ALL
(select count(emp_id) as Opening_HC from hcdata where status = "Moved" 

and DOJ <='2014-11-02' and inactive_date >= '2014-11-02' and 

sub_department='Sub_dep_07' and production_support='prod_sup-02')
UNION ALL
(select count(emp_id) as Opening_HC from hcdata where status = 

"Attrition" and DOJ <='2014-11-02' and inactive_date >= '2014-11-02' 

and sub_department='Sub_dep_07' and production_support='prod_sup-

02'))t1) as Opening_HC, (select count(emp_id) from hcdata where 

sub_department='Sub_dep_07' and production_support='prod_sup-02' and 

status='Attrite'and inactive_date between '2014-11-02' and  '2014-11-

08') as Attrition, (select count(emp_id) from hcdata where 

sub_department='Sub_dep_07' and production_support='prod_sup-02' and 

status='Moved' and inactive_date between '2014-11-02' and  '2014-11-

08') as Moved,(select count(emp_id) from hcdata where 

sub_department='Sub_dep_07' and production_support='prod_sup-02' and 

sub_department = 'Sub_dep_07' and   DOJ between '2014-11-02' and  

'2014-11-08') as Addition

现在我要寻找的是关闭\u HC、实体\u损耗%&流程\u损耗%

计算应为：

关闭\u HC=打开\u HC+添加-消耗-移动

实体损耗%=损耗/期初损耗+期末损耗/2

---

流程损耗%=损耗+移动/打开\u HC+关闭\u HC/2

我认为所有t1/打开\u HC都可以重写如下：

SELECT COUNT(emp_id) Opening_HC
  FROM hcdata
 WHERE (status = 'Active')
    OR (status IN('Moved','Attrition') AND inactive_date >= '2014-11-02') 
   AND DOJ <= '2014-11-02' 
   AND sub_department = 'Sub_dep_07' 
   AND production_support = 'prod_sup-02'

?

---

状态真的等同于“属性”吗？

格式做得很好。@Pankaj Link在办公室不工作：@juergend Sarcasm在互联网上很有效-我不明白你的意思guys@Strawberry-它给了我不正确的输出，在运行我的查询表之后是这样的：Opening_HC-Attrition-Moved-Addition，这些是即将出现的标题&也与数据匹配