그룹함수,DDL,테이블 제약조건

과제리뷰 <과제 문제 1> decode 풀이법: 쉼표가 있다 sql> select ename, job, sal, decode(job, 'ANALYST', sal*1.1, job, 'CLERK', sal*1.15, job, 'MANAGER', sal*1.2, sal) "급여인상액" from emp order by sal decs; to_char 응용법 sql> select ename, job, sal, to_char(decode(job, 'ANALYST', sal*1.1, job, 'CLERK', sal*1.15, job, 'MANAGER', sal*1.2, sal) , '$999,999') "급여인상액" , '$ 999,999') from emp order by sal decs; switch case: 쉼표가 없다 select empno, ename, sal to_char(case decode(job, when 'AL~', then sal*1.1, job, when 'CL~', th...