create table emp ( ename varchar2(20),
empno varchar2(10),
job varchar2(20),
hiredate date,
salary number (10,2),
comm number (10,2));

Then insert rows

create view emp_view as (
select ename, empno, job, hiredate,
decode ( ename, user, sal, 'KING',sal, 0) as sal,
decode ( ename, user, comm, 'KING', sal, 0) as comm
from emp);

I understand the basic decode( ename, 'kevin', MANAGER)
as if ename equal kevin then replace with MANAGER, but I don't understand decode( ename, user, sal, 'KING',sal, 0) as sal,

Please explain... thank you