Oracle中scott表结构与简单查询实例分析

select distinct job from emp;

select sal*12 [as] income from emp;

select empno ||','|| ename from emp;

select * from emp where job ='CLERK';

select * from emp where job!='CLERK'; 
select * from emp where job<>'CLERK';
select * from emp where NOT job='CLERK';

select * from emp where sal between 1500 and 3000; 

select * from emp where sal not between 1500 and 3000;

select * from emp where hiredate between '01-1月 -1981' and '31-12月 -81';

select * from emp where comm Is not null; 
select * from emp where not comm Is null;

select * from emp where empno in (7521,7844,5555);
select * from emp where empno not in (7521,7844,5555);

select * from emp where empno in (7521,7844,null);

select * from emp where not empno in (7521,7844,null);
select * from emp where empno not in (7521,7844,null);

select * from emp where ename like 'A%';

select * from emp where ename like '_A%'; 

select * from emp where ename like '%A%'; 

select * from emp where not ename like '%A%'; 
select * from emp where ename not like '%A%';

select * from emp where empno like '%%'

order by 字段 [ASC|DESC][,字段 [ASC|DESC]……];

select * from emp order by sal desc;

select * from emp order by sal desc,hiredate;