SQL> set linesize 200
SQL> select * from (select a.* ,row_number() over( order by empno) rn from emp a)
where rn=1 2
3 ;
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO DNAME RN
---------- ---------- --------- ---------- --------- ---------- ---------- ---------- -------------------------------------------------- ----------
7369 SMITH CLERK 7902 17-DEC-80 800 20 UFO