Ø The order of rows returned in the result of a query undefined.
Ø The order by clause can be used to sort the rows in the required order.
Ø The order by clause should be the last clause in the order of all clauses in the select statement.
Ø An expression or an alias can be specified to order by clauses for sorting.
Ø Default ordering of data is ascending
o Numbers à 0 - 9
o Dates à Earliest – Latest
o Strings à A – Z
o NULLS à Last
Ex:
- Select ename, job, deptno, hiredate from emp order by hiredate;
- Select ename, job, deptno, hiredate from emp order by hiredate desc;
- Select ename, job, sal from emp where job = ’MANAGER’ order by sal;
- Select ename,job, sal from emp where sal >= 2500 order by job, ename desc;
- Select empno, ename, sal, sal * 12 annsal from emp order by annsal;
- Select empno, ename, sal from emp order by deptno, sal, hiredate;
- Select empno, ename, sal from emp where sal >= 2000 order by hiredate, sal desc;