运算符 列名*1.1 case when... then ..when.. then ..else.. end

select  ENAME as '姓名',SAL as '原始工资', (SAL*1.1) as '涨工资10%'from emp where job='MANAGER';

#  经理涨薪%10，销售涨薪%50 其余不变 需要使用  case  when then when then else end
select 
    ename,
    job,
    sal as '原来的薪水',
    (case when job='MANAGER'then SAL*1.1 when job='SALESMAN' then sal*1.5 else sal end)as '最新的薪水'
from
    emp;