Calculate a calculate column in detail table in jdeveloper

Question

How to calculate sum of calcoulated column in detail table in jdeveloper Ex. In employee view add column as "calculate column type" his name is "avragesal" it calculate salary*20%

How can calculate sum "avragesal"for each department

For more explain In employee view

Dep_id.    Name.       Salary.    avragesal 
100        Jone.       1000.      200
100        XXX.        3000.      600
100        Zzz.        2000.      400
200        Ttt.        500.       100
200        Hhh.        700.       140
200        Ooo.        1200.      240

Iwana in department view

Dep_id.         Sumavragesal
100                     1200
200                      480

Answer 1

Kind of hard to understand what you are asking, but I think you want the sum of the average salary per department:

select dep_id, sum(avragesal)
from employee 
group by dep_id

The Oracle Docs is your friend.

Answer 2

It appears that your EMPLOYEE view is defined similarly to

CREATE OR REPLACE VIEW EMPLOYEE AS
  SELECT DEP_ID,
         NAME,
         SALARY
    FROM EMPLOYEE_TBL;

If this is the case (or something similar to this) then to add your AVRAGESAL column you'd do something like

CREATE OR REPLACE VIEW EMPLOYEE AS
  SELECT DEP_ID,
         NAME,
         SALARY,
         SALARY * 0.20 AS AVRAGESAL
    FROM EMPLOYEE_TBL;

Then to sum up EMPLOYEE.AVRAGESAL by department in the DEPARTMENT view you'd use something similar to

CREATE OR REPLACE VIEW DEPARTMENT AS
  SELECT DEP_ID,
         SUM(AVRAGESAL) AS AVRAGESAL
    FROM EMPLOYEE
    GROUP BY DEP_ID
    ORDER BY DEP_ID

You may need to modify this because I don't know what your EMPLOYEE view looks like, but hopefully this gives you an idea of how to proceed.