select ename,sal from emp ORDER BY sal DESC;
select empno, ename, sal from emp where sal >= 2000 and sal <= 3000;
select ename,sal from emp where ename LIKE ‘S%’;
select ename,sal,comm from emp where comm is NULL;
select AVG(sal) as avg_sal from emp;
select empno, ename, sal from emp where sal >= 2073;
select deptno, AVG(sal) as avg_sal from emp GROUP BY deptno;
select deptno, AVG(sal) as avg_sal from emp GROUP BY deptno having AVG(sal) >2500;
select count(*) from emp where deptno in (20,30)GROUP BY deptno;
select ename,sal from emp where CHAR_LENGTH(ename)=5