以下查詢均只涉及scott使用者下的emp表
1.查詢scott使用者下的所有表
> select * from tabs;> select * from emp;> select empno,ename,job,sal from emp;> select empno 編號, ename 姓名, job 工作, sal 工資 from emp;> select distinct job from emp;> select '編號：' || empno || '-姓名：' || ename || '-工作：' || job as 詳情 from emp;> select empno,ename,job,(sal + nvl(comm,0))*12 yearlysalary from emp;> select * from emp where sal >1500;> select ename,comm from emp where nvl(comm,0)>0;
> select ename,comm from emp where decode(comm,null,0,comm) > 0;
> select ename from emp where sal > 1500 or nvl(comm,0) > 0;
> select ename from emp where sal > 1500 or decode(comm,null,0,comm) > 0;
> select ename from emp where sal > 1500 and nvl(comm,0) > 0;
> select ename from emp where sal > 1500 and decode(comm,null,0,comm) > 0;
> select ename from emp where sal <= 1500 or nvl(comm,0) = 0;> select * from emp where sal >=1500 and sal <= 3000;> select sysdate from dual;> select * from emp where hiredate like '%81%';
> select * from emp where to_char(hiredate,'yyyy') = '1981';
> select * from emp where hiredate <= to_date('1981-12-31','yyyy-mm-dd') and hiredate >= to_date('1981-01-01','yyyy-mm-dd');
> select * from emp where hiredate between to_date('1981-01-01','yyyy-mm-dd') and to_date('1981-12-31','yyyy-mm-dd');
> select * from emp where ename like '__a%';> select * from emp where empno = '7369';> select * from emp where empno != '7369';
> select * from emp where empno <> '7369';
> select * from emp where empno in (7369,7900);> select * from emp where empno not in (7369,7900);> select * from emp order by sal;
> select * from emp order by sal asc;
> select * from emp order by sal desc;> select ename,job from emp where mgr is null;> select ename,job from emp where mgr is not null;> select e1.ename,e1.job,e2.ename from emp e1,emp e2 where e1.mgr = e2.empno(+);> select * from emp where deptno = 30;> select ename,empno,deptno from emp where job = 'clerk' order by deptno;> select * from emp where nvl(comm,0) > sal;> select * from emp where nvl(comm,0) < sal*0.4;> select * from emp where deptno = '10' and job = 'manager' union select * from emp where job = 'clerk' and deptno = '20';
> select * from emp where (deptno = '10' and job = 'manager') or (job = 'clerk' and deptno = '20');
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