@?/sqlplus/demo/demobld select table_Name from all_tables; desc emp select * from emp; select ename, empno from emp; select hiredate from emp; select to_char(hiredate,'YYYYMMDD') from emp; select (sysdate-hiredate)/365 from emp; select round((sysdate-hiredate)/365) from emp; desc dept select ename, dname from emp, dept; select ename, dname from emp, dept where emp.deptno = dept.deptno; set pages 50000 l (list sql in memory) / (reexecute sql from memory) select ename, dname from emp, dept where emp.deptno = dept.deptno and dept.dname = 'ACCOUNTING' select ename, sal, dname from emp, dept where emp.deptno = dept.deptno and dept.dname = 'ACCOUNTING' order by sal desc; select ename, sal, dname from emp, dept where emp.deptno = dept.deptno order by dname, sal desc; select sum(sal) from emp; SQL> select sum(sal) from emp; SUM(SAL) ---------- 29025 select deptno, sum(sal) from emp group by deptno; select deptno, max(sal) from emp group by deptno; select ename, deptno, max(sal) from emp group by deptno; select deptno, ename, sal from emp a where sal = (select max(sal) from emp b where a.deptno = b.deptno); select dname, sum(sal) from emp,dept where emp.deptno = dept.deptno group by dname; select dname, sum(sal) from emp,dept where emp.deptno (+) = dept.deptno group by dname; select count(*) from emp; update emp set sal = null where empno = 7782; select count(*) from emp where sal < 3000; select count(*) from emp where nvl(sal,0) >= 3000 or nvl(sal,0) < 3000; select * from emp where ename like 'M%'; select * from emp where ename like '%E%'; select * from emp where ename like 'ANDERS_N'; select * from emp where upper(ename) like 'ALL_N';