select ename,hiredates,job,sal,case when to_char(last_day(min(payday)),'day')='1' then min(payday)-2when to_char(last_day(min(payday)),'day')='2' then min(payday)-3when to_char(last_day(min(payday)),'day')='3' then min(payday)-4when to_char(last_day(min(payday)),'day')='4' then min(payday)-5when to_char(last_day(min(payday)),'day')='5' then min(payday)-6when to_char(last_day(min(payday)),'day')='6' then min(payday)when to_char(last_day(min(payday)),'day')='7' then min(payday)-1end paydayfrom emp group by ename,hiredates,job,sal